Time Difference
Add Time
Subtract Time
Select the operation you want to perform.
Enter duration (e.g., '2 weeks 3 days 8 hours').
Result Summary
—
Total Seconds: —
Total Minutes: —
Total Hours: —
Total Days: —
Formula Used: Duration = End Time – Start Time (or vice versa for add/subtract). Intermediate values are derived from total seconds.
Time Duration Visualization
Visualizes the breakdown of the calculated time duration into days, hours, minutes, and seconds.
Time Operation Comparison
Compares the start and end points or the effect of adding/subtracting time.
Time Calculation Breakdown
Unit
Value
Total Seconds
—
Total Minutes
—
Total Hours
—
Total Days
—
Total Weeks
—
Total Years (approx)
—
What is a Time Calculator App?
A time calculator app, often referred to as a date and time calculator or duration calculator, is a digital tool designed to perform various calculations involving dates and times. Its primary function is to help users determine the precise amount of time elapsed between two specific points in time, or to calculate future or past dates by adding or subtracting a specified duration. This powerful time calculator app simplifies complex temporal arithmetic, making it invaluable for professionals and individuals alike who need accurate timekeeping for scheduling, project management, historical analysis, event planning, and even personal milestone tracking. Essentially, it removes the potential for human error in calculating days, hours, minutes, and seconds across different dates.
Who Should Use It: Project managers tracking task durations, event planners scheduling events, students calculating study time or assignment deadlines, researchers analyzing historical data, developers estimating task completion times, and anyone needing to understand the span of time between two events or plan for future time-based occurrences.
Common Misconceptions: A common misconception is that time calculators are only for simple date differences. However, advanced time calculator apps can handle time zones, leap years, and complex duration additions/subtractions (e.g., '2 weeks, 3 days, 5 hours'). Another is that they are overly complicated; good time calculator apps offer intuitive interfaces for quick, accurate results.
Time Calculator App Formula and Mathematical Explanation
The core of any time calculator app revolves around the concept of temporal arithmetic. When calculating the difference between two points in time (t1 and t2), the fundamental formula is:
Duration = t2 – t1
Where 't1' is the start timestamp and 't2' is the end timestamp. Both 't1' and 't2' are typically represented as a total number of seconds elapsed since a reference point (like the Unix epoch: January 1, 1970, 00:00:00 UTC).
To calculate this effectively, the time calculator app converts the date and time inputs into a standardized numerical format, usually seconds. Then, it performs the subtraction.
For adding time, the formula becomes:
Future Time = t1 + Duration
And for subtracting time:
Past Time = t1 – Duration
The 'Duration' here is a specified interval (e.g., '5 days, 8 hours'). This interval is also converted into a total number of seconds before being added or subtracted from t1.
Once the total difference in seconds is calculated, it's then broken down into more human-readable units:
Total Minutes = Total Seconds / 60
Total Hours = Total Seconds / 3600
Total Days = Total Seconds / 86400
Total Weeks = Total Seconds / 604800
To get integer values for each unit, integer division and modulo operations are used. For example, to find the number of full days, hours, minutes, and remaining seconds:
Total Days = floor(Total Seconds / 86400)
Remaining Seconds after Days = Total Seconds % 86400
Total Hours = floor(Remaining Seconds after Days / 3600)
Remaining Seconds after Hours = Remaining Seconds after Days % 3600
Total Minutes = floor(Remaining Seconds after Hours / 60)
Remaining Seconds = Remaining Seconds after Hours % 60
Variable Table:
Variable Name
Meaning
Unit
Typical Range
t1 (Start Time)
The initial point in time.
Timestamp (e.g., seconds since epoch)
Varies widely, e.g., -2,147,483,648 to 2,147,483,647 (Unix 32-bit) or much larger for 64-bit systems.
t2 (End Time)
The final point in time.
Timestamp (e.g., seconds since epoch)
Varies widely, similar to t1.
Duration
The interval to add or subtract.
Seconds (internally converted)
Positive or negative values representing days, hours, minutes, seconds.
Total Seconds
The raw difference or converted duration in seconds.
Seconds
Can be any real number, positive or negative.
Total Minutes
Duration expressed in minutes.
Minutes
Derived from Total Seconds.
Total Hours
Duration expressed in hours.
Hours
Derived from Total Seconds.
Total Days
Duration expressed in days.
Days
Derived from Total Seconds.
Total Weeks
Duration expressed in weeks.
Weeks
Derived from Total Seconds.
Total Years (approx)
Duration expressed in years (365.25 days/year).
Years
Derived from Total Seconds.
Practical Examples (Real-World Use Cases)
Here are a couple of scenarios where a time calculator app is incredibly useful:
Example 1: Project Deadline Calculation
Scenario: A software development team estimates a new feature will take approximately 120 hours of work. They start working on Monday, October 21, 2024, at 9:00 AM. They want to know the estimated completion date and time, assuming they work 8 hours a day, Monday to Friday.
Inputs:
Start Date & Time: 2024-10-21 09:00 AM
Calculation Type: Add Time
Time to Add/Subtract: 120 hours
Using the Time Calculator App:
The calculator adds 120 hours (which is exactly 5 working days * 8 hours/day = 40 hours/week * 3 weeks) to the start time.
Outputs:
Estimated End Date & Time: Friday, November 8, 2024, 09:00 AM
Interpretation: This provides the team with a clear target deadline, allowing them to plan subsequent tasks and communicate progress effectively. The time calculator app handles the conversion of hours into days and weeks seamlessly.
Example 2: Calculating Time Between Events
Scenario: A historian is researching the duration of a specific historical period. They need to know the exact number of days between the end of one major event (e.g., Fall of Rome, often cited as 476 AD) and the beginning of another (e.g., Start of the Islamic Calendar, 622 AD).
Inputs:
Start Date & Time: 01-01-0476 00:00:00 (approximated start of the year)
End Date & Time: 01-01-0622 00:00:00 (approximated start of the year)
Calculation Type: Time Difference
Using the Time Calculator App:
The calculator computes the difference between these two Gregorian calendar dates.
Outputs (Approximate):
Total Duration: Approximately 146 years, 0 days, 0 hours, 0 minutes, 0 seconds. (More precisely, around 53,300+ days, accounting for leap years).
Total Days: 53,364 days (example calculation)
Interpretation: This gives a precise measure of the time gap, crucial for historical context and analysis. The time calculator app accurately handles the complexities of date differences over long periods.
How to Use This Time Calculator App
Using this advanced time calculator app is straightforward. Follow these steps:
Select Calculation Type: Choose whether you want to find the 'Time Difference' between two dates, 'Add Time' to a start date, or 'Subtract Time' from a start date.
Input Start Time: If calculating a difference or adding/subtracting time, enter the initial date and time using the `datetime-local` input field.
Input End Time: If calculating a difference, enter the final date and time.
Input Duration (for Add/Subtract): If you selected 'Add Time' or 'Subtract Time', a new field will appear. Enter the duration you wish to add or subtract. Use formats like '5 days 3 hours', '2 weeks 1 day', '72 hours', or '30 minutes'. The calculator will parse this input.
Click Calculate: Press the 'Calculate' button to see the results.
Interpreting Results:
Main Result: Displays the primary outcome (e.g., the total duration, or the future/past date and time).
Intermediate Values: Show the total duration broken down into seconds, minutes, hours, and days for clarity.
Time Breakdown Table: Provides a comprehensive view of the duration in various units (seconds, minutes, hours, days, weeks, and approximate years).
Charts: Visualize the components of the time duration or the relationship between time points.
Decision-Making Guidance: Use the results to set realistic deadlines, schedule meetings efficiently, understand project timelines, or analyze historical data. For instance, if a project is estimated to take 150 hours and the result shows it extends past a critical deadline, you know you need to adjust resources or scope.
Key Factors That Affect Time Calculator Results
While the core calculation is mathematical, several factors influence how we interpret and use the results from a time calculator app:
Daylight Saving Time (DST): DST shifts can cause clock times to jump forward or backward by an hour. A robust time calculator app might account for this if time zone support is included, but simple calculators often don't. This can lead to discrepancies if not considered, especially for durations crossing DST change dates.
Leap Years and Leap Seconds: Leap years add an extra day (February 29th), affecting day counts over multiple years. Leap seconds are occasionally added to UTC to keep it aligned with solar time. While less common in typical calculators, they highlight the complexity of precise timekeeping over long durations.
Time Zones: Calculating differences between times in different time zones requires accurate conversion factors and knowledge of DST rules for each zone. Our calculator assumes a single, consistent time context unless explicitly programmed for time zone conversions.
Definition of a "Day": Is it a 24-hour period, or a calendar day? For project management, workdays (e.g., 8 hours) are often more relevant than full 24-hour days. The interpretation of "Total Days" can vary based on context.
Accuracy of Input Data: The calculation is only as good as the input. Incorrect start/end times or misunderstood durations will lead to inaccurate results. Double-checking inputs is crucial.
Context of Calculation: Is the duration purely calendar-based, or does it involve working hours, business days, or holidays? A simple time calculator app provides raw chronological time; business-specific calculators might exclude weekends or holidays.
Approximation in "Year" Calculations: When converting to years, calculators often use an average year length (e.g., 365.25 days) to account for leap years. This is an approximation, and the exact number of days might differ slightly.
User Interface and Parsing Logic: For calculators that accept natural language input for durations (like '2 weeks 3 days'), the effectiveness depends heavily on the parsing logic of the time calculator app. Ambiguities in input format can lead to errors.
Frequently Asked Questions (FAQ)
Q1: Can this time calculator app handle time zones?
A: This specific calculator primarily works within a single assumed time context. For calculations involving different time zones, you would need to convert all inputs to a common zone (like UTC) beforehand or use a specialized time zone converter.
Q2: How does the calculator handle leap years?
A: When calculating differences over multiple years or converting to years, the calculator uses standard date/time libraries which inherently account for leap years in their internal calculations. For exact day counts between specific dates, it's accurate. The "Total Years" approximation uses an average year length.
Q3: What is the maximum duration this calculator can handle?
A: The maximum duration is limited by the underlying data types used by the browser's JavaScript date/time functions, which typically support dates far into the future and past (often up to year 275,760 AD or beyond). Precision might decrease for extremely large durations.
Q4: Can I use this to calculate my age?
A: Yes, by entering your birth date/time as the start time and the current date/time as the end time, and selecting "Time Difference", you can calculate your exact age in years, months, days, etc.
Q5: What format should I use for adding/subtracting time?
A: You can use natural language like "5 days 3 hours 15 minutes", "2 weeks", "48 hours", or combinations. The calculator attempts to parse common formats.
Q6: Does the calculator account for working hours or holidays?
A: No, this is a chronological time calculator. It calculates the total elapsed time. For business-specific calculations that exclude weekends or holidays, you would need a specialized business day calculator.
Q7: What does "Total Seconds" represent in the results?
A: It's the raw, total number of seconds representing the duration between the start and end times, or the duration you specified to add/subtract. It serves as the base unit for deriving other time units.
Q8: How precise is the "Total Years" calculation?
A: The "Total Years" calculation is typically an approximation, often based on 365.25 days per year to average out leap years. For exact day counts, refer to the "Total Days" or the full breakdown.
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var timeDurationChartInstance = null;
var timeOperationSvgInstance = null;
function parseDuration(durationString) {
var totalSeconds = 0;
if (!durationString) return 0;
durationString = durationString.toLowerCase();
var parts = durationString.match(/(\d+\.?\d*)\s*(years?|yrs?|y|months?|mos?|m|weeks?|wks?|w|days?|dys?|d|hours?|hrs?|h|minutes?|mins?|min|seconds?|secs?|s)/g);
if (!parts) return 0;
for (var i = 0; i < parts.length; i++) {
var match = parts[i].match(/(\d+\.?\d*)\s*(.*)/);
if (match) {
var value = parseFloat(match[1]);
var unit = match[2].trim();
switch (unit) {
case 'years':
case 'year':
case 'yrs':
case 'yr':
case 'y':
totalSeconds += value * 365.25 * 24 * 60 * 60; // Approximate years
break;
case 'months':
case 'month':
case 'mos':
case 'mo':
case 'm':
totalSeconds += value * 30.44 * 24 * 60 * 60; // Approximate months
break;
case 'weeks':
case 'week':
case 'wks':
case 'wk':
case 'w':
totalSeconds += value * 7 * 24 * 60 * 60;
break;
case 'days':
case 'day':
case 'dys':
case 'dy':
case 'd':
totalSeconds += value * 24 * 60 * 60;
break;
case 'hours':
case 'hour':
case 'hrs':
case 'hr':
case 'h':
totalSeconds += value * 60 * 60;
break;
case 'minutes':
case 'minute':
case 'mins':
case 'min':
totalSeconds += value * 60;
break;
case 'seconds':
case 'second':
case 'secs':
case 'sec':
case 's':
totalSeconds += value;
break;
}
}
}
return totalSeconds;
}
function calculateTime() {
var startInput = document.getElementById('startTime');
var endInput = document.getElementById('endTime');
var calcTypeSelect = document.getElementById('calculationType');
var timeToAddSubtractInput = document.getElementById('timeToAddSubtract');
var startTimeError = document.getElementById('startTimeError');
var endTimeError = document.getElementById('endTimeError');
var timeToAddSubtractError = document.getElementById('timeToAddSubtractError');
startTimeError.style.display = 'none';
endTimeError.style.display = 'none';
timeToAddSubtractError.style.display = 'none';
var calcType = calcTypeSelect.value;
var startDateStr = startInput.value;
var endDateStr = endInput.value;
var durationToAddSubtractStr = timeToAddSubtractInput.value;
var startValid = true;
var endValid = true;
var durationValid = true;
if (calcType !== 'add' && calcType !== 'subtract' && (!startDateStr || !endDateStr)) {
if (!startDateStr) {
startTimeError.textContent = 'Please enter a start time.';
startTimeError.style.display = 'block';
startValid = false;
}
if (!endDateStr) {
endTimeError.textContent = 'Please enter an end time.';
endTimeError.style.display = 'block';
endValid = false;
}
} else if ((calcType === 'add' || calcType === 'subtract') && !startDateStr) {
if (!startDateStr) {
startTimeError.textContent = 'Please enter a start time.';
startTimeError.style.display = 'block';
startValid = false;
}
}
if ((calcType === 'add' || calcType === 'subtract') && !durationToAddSubtractStr) {
timeToAddSubtractError.textContent = 'Please enter the duration to add or subtract.';
timeToAddSubtractError.style.display = 'block';
durationValid = false;
}
if (!startValid || !endValid || !durationValid) {
return;
}
var startDateTime = startDateStr ? new Date(startDateStr) : null;
var endDateTime = endDateStr ? new Date(endDateStr) : null;
var durationToAddSubtractSeconds = 0;
if (durationToAddSubtractStr) {
durationToAddSubtractSeconds = parseDuration(durationToAddSubtractStr);
if (isNaN(durationToAddSubtractSeconds)) {
timeToAddSubtractError.textContent = 'Invalid duration format. Use examples like "5 days 3 hours".';
timeToAddSubtractError.style.display = 'block';
return;
}
}
var mainResult = '–';
var totalSeconds = 0;
var resultDateTime = null;
var operationType = '';
if (calcType === 'difference') {
if (!startDateTime || !endDateTime) return;
if (endDateTime < startDateTime) {
timeToAddSubtractError.textContent = 'End time must be after start time for difference calculation.';
timeToAddSubtractError.style.display = 'block';
return;
}
operationType = 'Difference';
totalSeconds = Math.floor((endDateTime.getTime() – startDateTime.getTime()) / 1000);
mainResult = formatDuration(totalSeconds);
} else if (calcType === 'add') {
if (!startDateTime) return;
if (isNaN(durationToAddSubtractSeconds)) return; // Already validated above but good for safety
operationType = 'Addition';
var durationToAddMilliseconds = durationToAddSubtractSeconds * 1000;
resultDateTime = new Date(startDateTime.getTime() + durationToAddMilliseconds);
mainResult = resultDateTime.toLocaleString();
totalSeconds = durationToAddSubtractSeconds; // Show the duration itself
} else if (calcType === 'subtract') {
if (!startDateTime) return;
if (isNaN(durationToAddSubtractSeconds)) return;
operationType = 'Subtraction';
var durationToSubtractMilliseconds = durationToAddSubtractSeconds * 1000;
resultDateTime = new Date(startDateTime.getTime() – durationToSubtractMilliseconds);
mainResult = resultDateTime.toLocaleString();
totalSeconds = -durationToAddSubtractSeconds; // Show negative duration
}
updateResults(totalSeconds, mainResult, operationType, resultDateTime);
updateChart(totalSeconds);
updateSvgChart(startDateTime, endDateTime, resultDateTime, durationToAddSubtractSeconds, calcType);
updateTable(totalSeconds, durationToAddSubtractSeconds, calcType);
}
function formatDuration(totalSeconds) {
if (totalSeconds === null || isNaN(totalSeconds)) return '–';
var isNegative = totalSeconds 0) parts.push(totalDays + "d");
if (hours > 0) parts.push(hours + "h");
if (minutes > 0) parts.push(minutes + "m");
if (seconds > 0 || totalSeconds === 0) parts.push(seconds + "s"); // Show seconds even if 0 if duration is 0
if (parts.length === 0 && totalSeconds === 0) return "0 seconds";
if (parts.length === 0) return "Less than 1 second"; // Should not happen with floor logic, but safe
return formatted + parts.join(" ");
}
function updateResults(totalSeconds, mainResult, operationType, resultDateTime) {
document.getElementById('mainResult').textContent = mainResult;
var intermediateTotalSeconds = totalSeconds;
var intermediateTotalMinutes = Math.floor(Math.abs(totalSeconds) / 60);
var intermediateTotalHours = Math.floor(Math.abs(totalSeconds) / 3600);
var intermediateTotalDays = Math.floor(Math.abs(totalSeconds) / 86400);
document.getElementById('intermediateTotalSeconds').textContent = 'Total Seconds: ' + (operationType === 'Difference' ? totalSeconds : Math.abs(totalSeconds));
document.getElementById('intermediateTotalMinutes').textContent = 'Total Minutes: ' + intermediateTotalMinutes;
document.getElementById('intermediateTotalHours').textContent = 'Total Hours: ' + intermediateTotalHours;
document.getElementById('intermediateTotalDays').textContent = 'Total Days: ' + intermediateTotalDays;
var formulaDiv = document.querySelector('.formula-explanation');
if (operationType === 'Difference') {
formulaDiv.innerHTML = 'Formula Used: Duration = End Time – Start Time. Intermediate values are derived from the total seconds difference.';
} else if (operationType === 'Addition') {
formulaDiv.innerHTML = 'Formula Used: Future Time = Start Time + Duration. Result shown is the calculated future date/time. Duration breakdown is provided.';
} else if (operationType === 'Subtraction') {
formulaDiv.innerHTML = 'Formula Used: Past Time = Start Time – Duration. Result shown is the calculated past date/time. Duration breakdown is provided.';
}
}
function updateChart(totalSeconds) {
var ctx = document.getElementById('timeDurationChart').getContext('2d');
if (timeDurationChartInstance) {
timeDurationChartInstance.destroy();
}
var absSeconds = Math.abs(totalSeconds);
var days = Math.floor(absSeconds / 86400);
var remainingSecondsAfterDays = absSeconds % 86400;
var hours = Math.floor(remainingSecondsAfterDays / 3600);
var remainingSecondsAfterHours = remainingSecondsAfterDays % 3600;
var minutes = Math.floor(remainingSecondsAfterHours / 60);
var seconds = Math.floor(remainingSecondsAfterHours % 60);
var data = {
labels: ['Days', 'Hours', 'Minutes', 'Seconds'],
datasets: [{
label: 'Duration Breakdown',
data: [days, hours, minutes, seconds],
backgroundColor: [
'rgba(0, 74, 153, 0.6)', // Blue
'rgba(40, 167, 69, 0.6)', // Green
'rgba(255, 193, 7, 0.6)', // Yellow
'rgba(220, 53, 69, 0.6)' // Red
],
borderColor: [
'rgba(0, 74, 153, 1)',
'rgba(40, 167, 69, 1)',
'rgba(255, 193, 7, 1)',
'rgba(220, 53, 69, 1)'
],
borderWidth: 1
}]
};
// Check if canvas element exists
if (!ctx) {
console.error("Canvas element not found!");
return;
}
// Dynamically set canvas height based on content or aspect ratio
// For a simple bar chart, a fixed height might be sufficient or calculated based on labels/data
var canvas = document.getElementById('timeDurationChart');
canvas.height = 250; // Adjust height as needed
timeDurationChartInstance = new Chart(ctx, {
type: 'bar',
data: data,
options: {
responsive: true,
maintainAspectRatio: false, // Allows setting custom height/width
plugins: {
legend: {
position: 'top',
},
title: {
display: true,
text: 'Time Component Breakdown'
}
},
scales: {
y: {
beginAtZero: true,
title: {
display: true,
text: 'Value'
}
}
}
}
});
}
// Placeholder for SVG chart generation
function updateSvgChart(startDateTime, endDateTime, resultDateTime, durationToAddSubtractSeconds, calcType) {
var svgContainer = document.getElementById('timeOperationSvg');
if (!svgContainer) return;
svgContainer.innerHTML = "; // Clear previous content
var svgNS = "http://www.w3.org/2000/svg";
var width = svgContainer.clientWidth;
var height = svgContainer.clientHeight;
var margin = {top: 40, right: 20, bottom: 30, left: 60};
var innerWidth = width – margin.left – margin.right;
var innerHeight = height – margin.top – margin.bottom;
// — Basic SVG structure setup —
var svg = document.createElementNS(svgNS, "svg");
svg.setAttribute("width", width);
svg.setAttribute("height", height);
svg.setAttribute("viewBox", `0 0 ${width} ${height}`);
svgContainer.appendChild(svg);
var chartGroup = document.createElementNS(svgNS, "g");
chartGroup.setAttribute("transform", `translate(${margin.left},${margin.top})`);
svg.appendChild(chartGroup);
// — Scales —
var xScale;
var timePoints = [];
if (calcType === 'difference') {
if (startDateTime && endDateTime) {
timePoints = [startDateTime.getTime(), endDateTime.getTime()];
} else {
timePoints = [new Date().getTime(), new Date().getTime() + 86400000]; // Default if inputs missing
}
} else if (calcType === 'add') {
if (startDateTime && resultDateTime) {
timePoints = [startDateTime.getTime(), resultDateTime.getTime()];
} else {
timePoints = [new Date().getTime(), new Date().getTime() + 86400000];
}
} else if (calcType === 'subtract') {
if (startDateTime && resultDateTime) {
// Ensure chronological order for scale
timePoints = [resultDateTime.getTime(), startDateTime.getTime()];
} else {
timePoints = [new Date().getTime() – 86400000, new Date().getTime()];
}
} else { // Default to a day
timePoints = [new Date().getTime(), new Date().getTime() + 86400000];
}
var minTime = Math.min(…timePoints);
var maxTime = Math.max(…timePoints);
xScale = d3.scaleTime()
.domain([minTime, maxTime])
.range([0, innerWidth]);
// — Axes —
var xAxis = d3.axisBottom(xScale)
.ticks(5) // Adjust number of ticks
.tickFormat(d3.timeFormat("%Y-%m-%d %H:%M")); // Format ticks
chartGroup.append(document.createElementNS(svgNS, "g"))
.attr("transform", `translate(0,${innerHeight})`)
.call(xAxis);
// Add Y-axis label (simple representation)
chartGroup.append("text")
.attr("text-anchor", "middle")
.attr("x", innerWidth / 2)
.attr("y", innerHeight + margin.bottom – 10)
.text("Time Progression");
// — Data Series (Lines/Points) —
if (calcType === 'difference') {
// Line for start to end
var lineGenerator = d3.line()
.x(d => xScale(d.time))
.y(d => innerHeight); // Flat line for simplicity
var lineData = [
{ time: startDateTime ? startDateTime.getTime() : new Date().getTime(), value: 0 },
{ time: endDateTime ? endDateTime.getTime() : new Date().getTime() + 86400000, value: 0 }
];
var path = document.createElementNS(svgNS, "path");
path.setAttribute("d", lineGenerator(lineData));
path.setAttribute("stroke", "var(–primary-color)");
path.setAttribute("stroke-width", "2");
path.setAttribute("fill", "none");
chartGroup.appendChild(path);
// Start point
var startCircle = document.createElementNS(svgNS, "circle");
startCircle.setAttribute("cx", xScale(startDateTime ? startDateTime.getTime() : new Date().getTime()));
startCircle.setAttribute("cy", innerHeight);
startCircle.setAttribute("r", "5");
startCircle.setAttribute("fill", "var(–primary-color)");
chartGroup.appendChild(startCircle);
// End point
var endCircle = document.createElementNS(svgNS, "circle");
endCircle.setAttribute("cx", xScale(endDateTime ? endDateTime.getTime() : new Date().getTime() + 86400000));
endCircle.setAttribute("cy", innerHeight);
endCircle.setAttribute("r", "5");
endCircle.setAttribute("fill", "var(–success-color)");
chartGroup.appendChild(endCircle);
// Add title
chartGroup.append("text")
.attr("x", innerWidth / 2)
.attr("y", -10)
.attr("text-anchor", "middle")
.style("font-size", "16px")
.style("font-weight", "bold")
.text("Time Difference Visualization");
} else if (calcType === 'add') {
// Line from start to result
var lineGenerator = d3.line()
.x(d => xScale(d.time))
.y(d => innerHeight);
var lineData = [
{ time: startDateTime ? startDateTime.getTime() : new Date().getTime(), value: 0 },
{ time: resultDateTime ? resultDateTime.getTime() : new Date().getTime() + 86400000, value: 0 }
];
var path = document.createElementNS(svgNS, "path");
path.setAttribute("d", lineGenerator(lineData));
path.setAttribute("stroke", "var(–primary-color)");
path.setAttribute("stroke-width", "2");
path.setAttribute("fill", "none");
chartGroup.appendChild(path);
// Start point
var startCircle = document.createElementNS(svgNS, "circle");
startCircle.setAttribute("cx", xScale(startDateTime ? startDateTime.getTime() : new Date().getTime()));
startCircle.setAttribute("cy", innerHeight);
startCircle.setAttribute("r", "5");
startCircle.setAttribute("fill", "var(–primary-color)");
chartGroup.appendChild(startCircle);
// Result point
var resultCircle = document.createElementNS(svgNS, "circle");
resultCircle.setAttribute("cx", xScale(resultDateTime ? resultDateTime.getTime() : new Date().getTime() + 86400000));
resultCircle.setAttribute("cy", innerHeight);
resultCircle.setAttribute("r", "5");
resultCircle.setAttribute("fill", "var(–success-color)");
chartGroup.appendChild(resultCircle);
// Add title
chartGroup.append("text")
.attr("x", innerWidth / 2)
.attr("y", -10)
.attr("text-anchor", "middle")
.style("font-size", "16px")
.style("font-weight", "bold")
.text("Time Addition Visualization");
} else if (calcType === 'subtract') {
// Line from result to start
var lineGenerator = d3.line()
.x(d => xScale(d.time))
.y(d => innerHeight);
var lineData = [
{ time: resultDateTime ? resultDateTime.getTime() : new Date().getTime() – 86400000, value: 0 },
{ time: startDateTime ? startDateTime.getTime() : new Date().getTime(), value: 0 }
];
var path = document.createElementNS(svgNS, "path");
path.setAttribute("d", lineGenerator(lineData));
path.setAttribute("stroke", "var(–primary-color)");
path.setAttribute("stroke-width", "2");
path.setAttribute("fill", "none");
chartGroup.appendChild(path);
// Result point (past)
var resultCircle = document.createElementNS(svgNS, "circle");
resultCircle.setAttribute("cx", xScale(resultDateTime ? resultDateTime.getTime() : new Date().getTime() – 86400000));
resultCircle.setAttribute("cy", innerHeight);
resultCircle.setAttribute("r", "5");
resultCircle.setAttribute("fill", "var(–success-color)");
chartGroup.appendChild(resultCircle);
// Start point
var startCircle = document.createElementNS(svgNS, "circle");
startCircle.setAttribute("cx", xScale(startDateTime ? startDateTime.getTime() : new Date().getTime()));
startCircle.setAttribute("cy", innerHeight);
startCircle.setAttribute("r", "5");
startCircle.setAttribute("fill", "var(–primary-color)");
chartGroup.appendChild(startCircle);
// Add title
chartGroup.append("text")
.attr("x", innerWidth / 2)
.attr("y", -10)
.attr("text-anchor", "middle")
.style("font-size", "16px")
.style("font-weight", "bold")
.text("Time Subtraction Visualization");
}
// — Legend —
if (calcType === 'difference') {
// Start Point Legend
var startLegendGroup = document.createElementNS(svgNS, "g");
startLegendGroup.setAttribute("transform", `translate(10, ${margin.top – 30})`);
chartGroup.appendChild(startLegendGroup);
startLegendGroup.append("rect")
.attr("width", 15)
.attr("height", 15)
.attr("fill", "var(–primary-color)");
startLegendGroup.append("text")
.attr("x", 20)
.attr("y", 12)
.text("Start Time");
// End Point Legend
var endLegendGroup = document.createElementNS(svgNS, "g");
endLegendGroup.setAttribute("transform", `translate(100, ${margin.top – 30})`);
chartGroup.appendChild(endLegendGroup);
endLegendGroup.append("rect")
.attr("width", 15)
.attr("height", 15)
.attr("fill", "var(–success-color)");
endLegendGroup.append("text")
.attr("x", 20)
.attr("y", 12)
.text("End Time");
} else if (calcType === 'add') {
// Start Point Legend
var startLegendGroup = document.createElementNS(svgNS, "g");
startLegendGroup.setAttribute("transform", `translate(10, ${margin.top – 30})`);
chartGroup.appendChild(startLegendGroup);
startLegendGroup.append("rect")
.attr("width", 15)
.attr("height", 15)
.attr("fill", "var(–primary-color)");
startLegendGroup.append("text")
.attr("x", 20)
.attr("y", 12)
.text("Start Time");
// Result Point Legend
var resultLegendGroup = document.createElementNS(svgNS, "g");
resultLegendGroup.setAttribute("transform", `translate(100, ${margin.top – 30})`);
chartGroup.appendChild(resultLegendGroup);
resultLegendGroup.append("rect")
.attr("width", 15)
.attr("height", 15)
.attr("fill", "var(–success-color)");
resultLegendGroup.append("text")
.attr("x", 20)
.attr("y", 12)
.text("Result Time");
} else if (calcType === 'subtract') {
// Start Point Legend
var startLegendGroup = document.createElementNS(svgNS, "g");
startLegendGroup.setAttribute("transform", `translate(10, ${margin.top – 30})`);
chartGroup.appendChild(startLegendGroup);
startLegendGroup.append("rect")
.attr("width", 15)
.attr("height", 15)
.attr("fill", "var(–primary-color)");
startLegendGroup.append("text")
.attr("x", 20)
.attr("y", 12)
.text("Start Time");
// Result Point Legend
var resultLegendGroup = document.createElementNS(svgNS, "g");
resultLegendGroup.setAttribute("transform", `translate(100, ${margin.top – 30})`);
chartGroup.appendChild(resultLegendGroup);
resultLegendGroup.append("rect")
.attr("width", 15)
.attr("height", 15)
.attr("fill", "var(–success-color)");
resultLegendGroup.append("text")
.attr("x", 20)
.attr("y", 12)
.text("Result Time");
}
}
function updateTable(totalSeconds, durationToAddSubtractSeconds, calcType) {
var tbody = document.getElementById('timeBreakdownTableBody');
tbody.innerHTML = "; // Clear previous content
var absSeconds = Math.abs(totalSeconds); // Use absolute for breakdown units
var data = {
'Total Seconds': absSeconds,
'Total Minutes': Math.floor(absSeconds / 60),
'Total Hours': Math.floor(absSeconds / 3600),
'Total Days': Math.floor(absSeconds / 86400),
'Total Weeks': Math.floor(absSeconds / 604800),
'Total Years (approx)': Math.floor(absSeconds / (365.25 * 86400))
};
for (var unit in data) {
var row = tbody.insertRow();
var cellUnit = row.insertCell();
var cellValue = row.insertCell();
cellUnit.textContent = unit;
cellValue.textContent = data[unit].toLocaleString();
}
}
function resetCalculator() {
document.getElementById('startTime').value = ";
document.getElementById('endTime').value = ";
document.getElementById('calculationType').value = 'difference';
document.getElementById('timeToAddSubtract').value = ";
document.getElementById('timeToAddSubtractContainer').style.display = 'none';
document.getElementById('startTimeError').textContent = ";
document.getElementById('startTimeError').style.display = 'none';
document.getElementById('endTimeError').textContent = ";
document.getElementById('endTimeError').style.display = 'none';
document.getElementById('timeToAddSubtractError').textContent = ";
document.getElementById('timeToAddSubtractError').style.display = 'none';
document.getElementById('mainResult').textContent = '–';
document.getElementById('intermediateTotalSeconds').textContent = 'Total Seconds: –';
document.getElementById('intermediateTotalMinutes').textContent = 'Total Minutes: –';
document.getElementById('intermediateTotalHours').textContent = 'Total Hours: –';
document.getElementById('intermediateTotalDays').textContent = 'Total Days: –';
document.querySelector('.formula-explanation').innerHTML = 'Formula Used: Duration = End Time – Start Time. Intermediate values are derived from total seconds.';
if (timeDurationChartInstance) {
timeDurationChartInstance.destroy();
timeDurationChartInstance = null;
}
document.getElementById('timeOperationSvg').innerHTML = "; // Clear SVG
var tableBody = document.getElementById('timeBreakdownTableBody');
tableBody.innerHTML = ";
var defaultRows = [
'Total Seconds', 'Total Minutes', 'Total Hours', 'Total Days', 'Total Weeks', 'Total Years (approx)'
];
defaultRows.forEach(function(text) {
var row = tableBody.insertRow();
var cellUnit = row.insertCell();
var cellValue = row.insertCell();
cellUnit.textContent = text;
cellValue.textContent = '–';
});
// Show/hide the SVG chart based on selection
var calcTypeSelect = document.getElementById('calculationType');
toggleDurationInput(calcTypeSelect.value);
}
function copyResults() {
var mainResult = document.getElementById('mainResult').textContent;
var intermediateSeconds = document.getElementById('intermediateTotalSeconds').textContent;
var intermediateMinutes = document.getElementById('intermediateTotalMinutes').textContent;
var intermediateHours = document.getElementById('intermediateTotalHours').textContent;
var intermediateDays = document.getElementById('intermediateTotalDays').textContent;
var formula = document.querySelector('.formula-explanation').textContent;
var summary = `— Time Calculation Results —\n\n`;
summary += `Primary Result: ${mainResult}\n`;
summary += `${intermediateSeconds}\n`;
summary += `${intermediateMinutes}\n`;
summary += `${intermediateHours}\n`;
summary += `${intermediateDays}\n`;
summary += `\n${formula}`;
// Use Clipboard API
navigator.clipboard.writeText(summary).then(function() {
// Optionally show a confirmation message
var copyButton = document.querySelector('button.success-button');
var originalText = copyButton.textContent;
copyButton.textContent = 'Copied!';
setTimeout(function() {
copyButton.textContent = originalText;
}, 1500);
}).catch(function(err) {
console.error('Failed to copy: ', err);
// Fallback for older browsers or environments where clipboard API is restricted
var textArea = document.createElement("textarea");
textArea.value = summary;
textArea.style.position = "fixed"; // Avoid scrolling to bottom
textArea.style.opacity = "0";
document.body.appendChild(textArea);
textArea.focus();
textArea.select();
try {
var successful = document.execCommand('copy');
var msg = successful ? 'Copied!' : 'Copy failed!';
var copyButton = document.querySelector('button.success-button');
copyButton.textContent = msg;
setTimeout(function() {
copyButton.textContent = 'Copy Results';
}, 1500);
} catch (err) {
console.error('Fallback copy failed: ', err);
var copyButton = document.querySelector('button.success-button');
copyButton.textContent = 'Copy Failed!';
setTimeout(function() {
copyButton.textContent = 'Copy Results';
}, 1500);
}
document.body.removeChild(textArea);
});
}
// Helper function to toggle the visibility of the duration input
function toggleDurationInput(calcType) {
var durationInputContainer = document.getElementById('timeToAddSubtractContainer');
if (calcType === 'add' || calcType === 'subtract') {
durationInputContainer.style.display = 'block';
} else {
durationInputContainer.style.display = 'none';
document.getElementById('timeToAddSubtract').value = "; // Clear value when hidden
document.getElementById('timeToAddSubtractError').style.display = 'none';
}
}
// Event listener for calculation type change
document.getElementById('calculationType').addEventListener('change', function() {
toggleDurationInput(this.value);
// Optionally clear results when type changes, or recalculate if inputs are valid
// calculateTime(); // Uncomment to recalculate immediately on type change
});
// Initial setup for the duration input visibility
document.addEventListener('DOMContentLoaded', function() {
var initialCalcType = document.getElementById('calculationType').value;
toggleDurationInput(initialCalcType);
// Ensure d3 library is loaded for SVG chart
if (typeof d3 === 'undefined') {
console.error("D3.js is required for the SVG chart but not loaded.");
document.getElementById('timeOperationSvg').style.display = 'none'; // Hide SVG chart if d3 is missing
} else {
updateSvgChart(null, null, null, 0, 'difference'); // Initial empty SVG chart
}
});