Instantly convert between common metric units of weight, including milligrams (mg), grams (g), kilograms (kg), and tonnes (t). Get accurate conversions for your needs.
Chart showing input value against converted value across different units.
Metric Unit Conversions Summary
Key Metric Weight Conversions
Unit
To Grams (g)
To Kilograms (kg)
To Tonnes (t)
Milligram (mg)
1 mg = 0.001 g
1 mg = 0.000001 kg
1 mg = 0.000000001 t
Gram (g)
1 g = 1 g
1 g = 0.001 kg
1 g = 0.000001 t
Kilogram (kg)
1 kg = 1000 g
1 kg = 1 kg
1 kg = 0.001 t
Tonne (t)
1 t = 1,000,000 g
1 t = 1000 kg
1 t = 1 t
{primary_keyword}
The convert metric units of weight calculator is an invaluable tool for anyone needing to accurately switch between different units within the metric system. Metric units of weight are based on powers of ten, making conversions straightforward once the relationships are understood. This tool simplifies that process, providing instant results for common units such as milligrams (mg), grams (g), kilograms (kg), and tonnes (t). Whether you're a student, a scientist, a chef, an engineer, or simply someone dealing with measurements, this {primary_keyword} calculator ensures precision and saves valuable time.
The primary users of a {primary_keyword} calculator include:
Students and Educators: Assisting with physics, chemistry, and mathematics lessons.
Scientists and Researchers: Ensuring accurate data recording and analysis in laboratories.
Culinary Professionals: Converting recipes or ingredient measurements.
Engineers and Manufacturers: Working with material specifications and product weights.
Logistics and Shipping Personnel: Calculating payloads and shipping weights.
Health and Fitness Enthusiasts: Tracking weight changes or dietary intake.
A common misconception is that metric conversions are always complicated. However, due to the base-10 nature of the metric system, conversions are typically achieved by multiplying or dividing by powers of 10 (10, 100, 1000, etc.), essentially shifting the decimal point. This {primary_keyword} tool automates these calculations.
{primary_keyword} Formula and Mathematical Explanation
The metric system is a globally recognized system of measurement that uses base units and prefixes to denote multiples or submultiples of those units. For weight (or more accurately, mass, though 'weight' is commonly used), the base unit is the gram (g). Other units are derived by applying prefixes:
Milligram (mg): 1/1,000,000 of a kilogram, or 1/1000 of a gram.
Gram (g): The base unit.
Kilogram (kg): 1000 grams. This is the SI base unit of mass.
Tonne (t): 1000 kilograms.
The core principle behind the {primary_keyword} conversion is understanding these multiplicative factors.
Conversion Formulas
To convert from any unit to another, we first convert to a common base unit (like grams) and then convert to the target unit. Alternatively, we can use direct conversion factors.
General Formula:
Converted Value = Original Value × (Conversion Factor from Original Unit to Target Unit)
Let's break down the conversion factors relative to grams (g):
Milligram (mg) to Grams (g): Multiply by 0.001 (or divide by 1000)
Gram (g) to Grams (g): Multiply by 1
Kilogram (kg) to Grams (g): Multiply by 1000
Tonne (t) to Grams (g): Multiply by 1,000,000
Variable Explanations
In our calculator, the variables are:
Value to Convert: The numerical quantity of weight you start with.
From Unit: The unit of the initial value (e.g., kg, g, mg, t).
To Unit: The desired unit for the converted value (e.g., kg, g, mg, t).
Converted Value: The final numerical quantity in the target unit.
Intermediate Values: These typically represent the value converted into grams and kilograms to show the steps.
Variables Table
Metric Weight Variables
Variable
Meaning
Unit
Typical Range
Value to Convert
The numerical amount of weight being converted.
Unit selected in 'From Unit'
Non-negative number
From Unit
The source unit of weight.
Unit Type (mg, g, kg, t)
mg, g, kg, t
To Unit
The target unit of weight.
Unit Type (mg, g, kg, t)
mg, g, kg, t
Converted Value
The result of the conversion in the 'To Unit'.
Unit selected in 'To Unit'
Depends on input and units
Value in Grams (g)
The input value expressed in grams.
g
Can be very small (mg) or very large (t)
Value in Kilograms (kg)
The input value expressed in kilograms.
kg
Can be very small (mg) or very large (t)
Practical Examples (Real-World Use Cases)
Here are some practical scenarios where the {primary_keyword} calculator is useful:
Example 1: Baking a Cake Recipe Adjustment
A recipe calls for 250 grams of flour, but you only have a digital scale that measures in kilograms. You need to know how much flour to use in kilograms.
Input Value: 250
From Unit: Grams (g)
To Unit: Kilograms (kg)
Calculation: To convert grams to kilograms, we divide by 1000.
250 g ÷ 1000 = 0.25 kg
Result: 250 grams is equal to 0.25 kilograms. This {primary_keyword} conversion helps you accurately measure ingredients when your tools use different units.
Example 2: Shipping a Small Package
You need to ship a small electronics component that weighs 1500 milligrams. The shipping service charges based on weight in kilograms. How much does the component weigh in kilograms?
Input Value: 1500
From Unit: Milligrams (mg)
To Unit: Kilograms (kg)
Calculation: To convert milligrams to kilograms, we need to go through grams. First, mg to g (divide by 1000), then g to kg (divide by 1000 again). This is equivalent to dividing by 1,000,000 (1000 × 1000).
1500 mg ÷ 1,000,000 = 0.0015 kg
Result: 1500 milligrams is equal to 0.0015 kilograms. This {primary_keyword} calculation is crucial for accurate shipping costs.
How to Use This {primary_keyword} Calculator
Using the {primary_keyword} calculator is designed to be intuitive and straightforward. Follow these simple steps:
Enter the Value: In the "Value to Convert" field, type the numerical weight you want to convert.
Select the 'From' Unit: Use the first dropdown menu ("From Unit") to choose the unit your initial weight is currently in (e.g., milligrams, grams, kilograms, tonnes).
Select the 'To' Unit: Use the second dropdown menu ("To Unit") to select the unit you want to convert your weight into.
Click 'Convert': Press the "Convert" button. The calculator will instantly display the results.
How to Read Results
Main Result: The most prominent number displayed is your converted weight in the "To Unit" you selected.
Intermediate Results: You'll see the weight expressed in grams and kilograms. These are useful for understanding the magnitude of the conversion and for cross-referencing.
Formula Explanation: A brief text explains the basic conversion principle used.
Decision-Making Guidance
The results from this {primary_keyword} calculator can inform various decisions:
Recipe Scaling: Adjust ingredient quantities accurately when changing measurement units.
Scientific Accuracy: Ensure data consistency across different measurement standards.
Material Estimation: Calculate required amounts of raw materials for projects.
Use the "Reset" button to clear all fields and start a new conversion. The "Copy Results" button allows you to easily transfer the main result, intermediate values, and key assumptions to another document or application.
Key Factors That Affect {primary_keyword} Results
While the mathematical conversion itself is precise, certain real-world factors and considerations are essential when interpreting or applying the results of a {primary_keyword} conversion:
Precision of Measurement Tools: The accuracy of your initial measurement directly impacts the reliability of the converted value. A scale that is not properly calibrated or has low precision will lead to inaccurate results, even with perfect conversion math.
Unit Definitions: Ensure you are using standard metric definitions. While rare in the metric system, slight variations in unit definitions could theoretically exist in historical or specialized contexts. This calculator uses standard SI definitions.
Context of Measurement: Weight (mass) is constant, but *weight* (the force due to gravity) can vary slightly depending on location (e.g., altitude, gravitational pull). However, for practical purposes like recipes or shipping, this difference is negligible, and the calculator assumes standard gravity.
Significant Figures: Be mindful of significant figures. If your initial measurement has limited precision (e.g., 5.2 g), the converted value should ideally reflect that precision (e.g., 0.0052 kg), rather than implying greater accuracy than is present.
Data Entry Errors: Simple mistakes like typing the wrong number or selecting the incorrect 'From' or 'To' unit are common. Always double-check your inputs before relying on the converted result. Our inline validation helps prevent some of these errors.
Environmental Conditions: For extremely precise scientific measurements, factors like humidity or temperature can slightly affect mass readings, especially for sensitive instruments. This calculator assumes standard ambient conditions.
Specific Industry Standards: Certain industries might have specific rounding rules or accepted tolerances for weight conversions. Always adhere to relevant industry guidelines when precision is critical.
Inflation (Indirect): While inflation doesn't directly change the mathematical conversion of units, it affects the cost associated with materials measured by weight. For example, if the price of gold is $60,000 per kg, converting that to grams ($60/g) helps in understanding smaller transaction values, which can be indirectly influenced by economic factors like inflation.
Frequently Asked Questions (FAQ)
Q1: What is the difference between mass and weight?
Technically, mass is the amount of matter in an object (measured in kg, g, etc.), while weight is the force of gravity acting on that mass (measured in Newtons). However, in everyday language and for practical purposes like this {primary_keyword} calculator, 'weight' is commonly used interchangeably with 'mass' when referring to metric units.
Q2: Is a tonne the same as a US ton?
No. A metric tonne (t) is 1000 kilograms. A US ton (short ton) is approximately 907.185 kilograms. They are different units.
Q3: How accurate is this calculator?
The calculator uses standard mathematical formulas for metric conversions. Its accuracy is limited only by the precision of your input value and the floating-point precision of the browser's JavaScript engine, which is generally very high for these calculations.
Q4: Can I convert weights outside the standard metric units (mg, g, kg, t)?
This specific {primary_keyword} calculator is designed only for the common metric units listed. For other units (like pounds, ounces, stones), you would need a different calculator.
Q5: What does it mean if my result is a very small or very large number?
It simply reflects the large difference in scale between the 'From' and 'To' units. For example, converting a large number of tonnes to milligrams will result in an extremely large number.
Q6: Why are grams and kilograms shown as intermediate results?
Grams (g) are the base unit for mass in the CGS system, and kilograms (kg) are the base unit for mass in the SI system. Showing conversions to these units provides a reference point and helps in understanding the scale of the measurement.
Q7: Can this calculator handle decimal inputs?
Yes, the calculator accepts decimal numbers for the "Value to Convert" field.
Q8: What should I do if I get an error message?
Error messages indicate invalid input. Typically, this means you've entered text instead of a number, a negative number (which doesn't make sense for weight), or potentially left a field blank if validation was stricter. Ensure you are entering a valid, non-negative numerical value.
var chartInstance = null;
function getConversionFactors() {
return {
mg: { to_g: 0.001, from_g: 1000 },
g: { to_g: 1, from_g: 1 },
kg: { to_g: 1000, from_g: 0.001 },
t: { to_g: 1000000, from_g: 0.000001 }
};
}
function validateInput(inputElement, allowDecimal, allowNegative, minValue, maxValue) {
var errorElement = document.getElementById(inputElement.id + 'Error');
var value = inputElement.value.trim();
errorElement.textContent = ";
if (value === ") {
errorElement.textContent = 'This field is required.';
return false;
}
if (!allowDecimal && value.includes('.')) {
errorElement.textContent = 'Please enter a whole number.';
return false;
}
var numValue = parseFloat(value);
if (isNaN(numValue)) {
errorElement.textContent = 'Please enter a valid number.';
return false;
}
if (!allowNegative && numValue < 0) {
errorElement.textContent = 'Value cannot be negative.';
return false;
}
if (minValue !== null && numValue maxValue) {
errorElement.textContent = 'Value cannot exceed ' + maxValue + '.';
return false;
}
return true;
}
function updateUnits() {
var fromUnitSelect = document.getElementById('fromUnit');
var toUnitSelect = document.getElementById('toUnit');
// Prevent selecting the same unit for both 'from' and 'to'
if (fromUnitSelect.value === toUnitSelect.value) {
// If 'from' was changed to match 'to', change 'to' back to something else
if (fromUnitSelect.id === document.activeElement.id) {
var options = toUnitSelect.options;
for (var i = 0; i < options.length; i++) {
if (options[i].value !== fromUnitSelect.value) {
toUnitSelect.value = options[i].value;
break;
}
}
} else { // If 'to' was changed to match 'from', change 'from' back
var options = fromUnitSelect.options;
for (var i = 0; i < options.length; i++) {
if (options[i].value !== toUnitSelect.value) {
fromUnitSelect.value = options[i].value;
break;
}
}
}
}
calculateConversion(); // Recalculate when units change
}
function calculateConversion() {
var valueToConvertInput = document.getElementById('valueToConvert');
var fromUnit = document.getElementById('fromUnit').value;
var toUnit = document.getElementById('toUnit').value;
if (!validateInput(valueToConvertInput, true, false, null, null)) {
document.getElementById('resultContainer').style.display = 'none';
return;
}
var valueToConvert = parseFloat(valueToConvertInput.value);
var conversionFactors = getConversionFactors();
var resultContainer = document.getElementById('resultContainer');
var mainResultSpan = document.getElementById('mainResult');
var resultGramsSpan = document.getElementById('resultGrams');
var resultKilogramsSpan = document.getElementById('resultKilograms');
var resultMilligramsSpan = document.getElementById('resultMilligrams');
var formulaExplanationDiv = document.getElementById('formulaExplanation');
// Convert input value to grams first
var valueInGrams = valueToConvert * conversionFactors[fromUnit].to_g;
// Convert grams to the target unit
var convertedValue = valueInGrams * conversionFactors[toUnit].from_g;
// Calculate intermediate values
var intermediateKilograms = valueInGrams * conversionFactors['kg'].from_g;
var intermediateMilligrams = valueInGrams * conversionFactors['mg'].from_g;
// Display results
mainResultSpan.textContent = formatNumber(convertedValue) + ' ' + toUnit;
resultGramsSpan.textContent = formatNumber(valueInGrams) + ' g';
resultKilogramsSpan.textContent = formatNumber(intermediateKilograms) + ' kg';
resultMilligramsSpan.textContent = formatNumber(intermediateMilligrams) + ' mg';
// Update formula explanation
formulaExplanationDiv.textContent = "To convert " + valueToConvert + " " + fromUnit + " to " + toUnit + ", we first convert to grams (" + fromUnit + " to g factor) and then to the target unit (g to " + toUnit + " factor).";
resultContainer.style.display = 'block';
updateChart(valueToConvert, fromUnit, convertedValue, toUnit, valueInGrams, intermediateKilograms, intermediateMilligrams);
}
function formatNumber(num) {
// Simple formatting, can be improved for scientific notation if needed
return parseFloat(num.toPrecision(10)).toString();
}
function resetCalculator() {
document.getElementById('valueToConvert').value = '1'; // Sensible default
document.getElementById('fromUnit').value = 'kg'; // Sensible default
document.getElementById('toUnit').value = 'g'; // Sensible default
// Clear error messages
document.getElementById('valueToConvertError').textContent = '';
document.getElementById('fromUnitError').textContent = '';
document.getElementById('toUnitError').textContent = '';
document.getElementById('resultContainer').style.display = 'none';
if (chartInstance) {
chartInstance.destroy();
chartInstance = null;
}
// Reset chart canvas (optional, if chart is destroyed and recreated)
var canvas = document.getElementById('conversionChart');
var ctx = canvas.getContext('2d');
ctx.clearRect(0, 0, canvas.width, canvas.height);
}
function copyResults() {
var mainResult = document.getElementById('mainResult').textContent;
var grams = document.getElementById('resultGrams').textContent;
var kgs = document.getElementById('resultKilograms').textContent;
var mgs = document.getElementById('resultMilligrams').textContent;
var formula = document.getElementById('formulaExplanation').textContent;
var resultText = "Conversion Result:\n";
resultText += "Main: " + mainResult + "\n";
resultText += "Intermediate Values:\n";
resultText += "- " + grams + "\n";
resultText += "- " + kgs + "\n";
resultText += "- " + mgs + "\n";
resultText += "Formula: " + formula + "\n";
resultText += "Assumptions: Standard metric conversions.";
try {
navigator.clipboard.writeText(resultText).then(function() {
alert('Results copied to clipboard!');
}, function(err) {
console.error('Async: Could not copy text: ', err);
// Fallback for older browsers or environments where clipboard API is not available
var textArea = document.createElement("textarea");
textArea.value = resultText;
textArea.style.position = "fixed"; // Avoid scrolling to bottom
document.body.appendChild(textArea);
textArea.focus();
textArea.select();
try {
var successful = document.execCommand('copy');
var msg = successful ? 'successful' : 'unsuccessful';
console.log('Fallback: Copying text command was ' + msg);
alert('Results copied to clipboard!');
} catch (err) {
console.error('Fallback: Oops, unable to copy', err);
alert('Failed to copy results. Please copy manually.');
}
document.body.removeChild(textArea);
});
} catch (e) {
console.error('Error using Clipboard API: ', e);
alert('Failed to copy results. Please copy manually.');
}
}
function updateChart(inputValue, fromUnit, convertedValue, toUnit, valueInGrams, intermediateKilograms, intermediateMilligrams) {
var ctx = document.getElementById('conversionChart').getContext('2d');
// Destroy previous chart instance if it exists
if (chartInstance) {
chartInstance.destroy();
}
var labels = ['Grams (g)', 'Kilograms (kg)', 'Milligrams (mg)'];
var inputValues = [];
var convertedValues = [];
// Calculate corresponding values in grams, kgs, and mgs for comparison
var factors = getConversionFactors();
// Base input value in its original unit
inputValues.push(inputValue * factors[fromUnit].to_g); // Represents input in grams
convertedValues.push(inputValue * factors[fromUnit].to_g); // Represents converted value in grams (if 'to' was g)
// Calculate value in kg for both input and output if different
var inputKg = inputValue * factors[fromUnit].from_g; // Input value in kg
var outputKg = convertedValue * factors[toUnit].from_g; // Output value in kg
// Calculate value in mg for both input and output if different
var inputMg = inputValue * factors[fromUnit].to_g * factors['mg'].from_g; // Input value in mg
var outputMg = convertedValue * factors[toUnit].to_g * factors['mg'].from_g; // Output value in mg
// Let's try to plot input vs output across standard units
// We will plot the input value converted to g, kg, mg
// And the output value converted to g, kg, mg
// If the 'toUnit' is 'g', then convertedValue is already in grams
// If the 'toUnit' is 'kg', then convertedValue is already in kg
// etc.
// For simplicity, let's plot the input value's equivalent in g, kg, mg
// and the output value's equivalent in g, kg, mg.
// This might be confusing if the 'toUnit' is far from g/kg/mg.
// A better approach: Plot the input value and the output value on a common scale.
// For the chart, let's compare the INPUT VALUE in its original unit VS the OUTPUT VALUE in its target unit.
// This requires a dynamic scale.
// Let's try plotting intermediate values for better context.
// We have valueInGrams, intermediateKilograms, intermediateMilligrams
// We need to show how the INPUT value compares to the OUTPUT value.
// Let's make the chart show the magnitude of the input vs output in grams.
// And perhaps add kg as a secondary comparison.
var dataSeries1 = [valueInGrams, intermediateKilograms * 1000, intermediateMilligrams / 1000]; // Input equivalent in g, kg, mg
var dataSeries2 = [convertedValue * factors[toUnit].to_g, convertedValue * factors[toUnit].from_g * 1000, convertedValue * factors[toUnit].to_g * factors['mg'].from_g]; // Output equivalent in g, kg, mg
// Ensure consistency: represent all as grams for the base scale.
// Input value in grams:
var inputInGrams = inputValue * factors[fromUnit].to_g;
// Output value in grams:
var outputInGrams = convertedValue * factors[toUnit].to_g;
// For comparative purposes on the chart, let's show the input and output values directly
// scaled appropriately. Or, let's plot them in their respective units if possible,
// but canvas needs numerical data.
// Let's use the intermediate gram and kilogram values, and the main result.
// Series 1: Input Value Equivalent across g, kg, mg
// Series 2: Output Value Equivalent across g, kg, mg
// We have:
// valueInGrams (input converted to grams)
// intermediateKilograms (input converted to kilograms)
// intermediateMilligrams (input converted to milligrams)
// Let's use these three for the input series.
// For the output series, we need to convert the FINAL convertedValue back to g, kg, mg.
var finalConvertedValueInGrams = convertedValue * factors[toUnit].to_g;
var finalConvertedValueInKgs = convertedValue * factors[toUnit].from_g;
var finalConvertedValueInMgs = convertedValue * factors[toUnit].to_g * factors['mg'].from_g;
// The chart will show:
// Label: "Input Value" | Series 1: [valueInGrams, intermediateKilograms, intermediateMilligrams]
// Label: "Converted Value" | Series 2: [finalConvertedValueInGrams, finalConvertedValueInKgs, finalConvertedValueInMgs]
// We need to ensure labels align. Let's use the intermediate values as the primary comparison points.
// Let's redefine the chart data to be clearer.
// We will show: Input value in Grams vs. Output value in Grams.
// And Input value in Kilograms vs. Output value in Kilograms.
// And Input value in Milligrams vs. Output value in Milligrams.
// This requires careful scaling and labels.
// Let's simplify: Plot the input value (in grams) and the output value (in grams).
// And the input value (in kg) and the output value (in kg).
var chartLabels = ['Grams Equivalent', 'Kilograms Equivalent', 'Milligrams Equivalent'];
var inputData = [
inputValue * factors[fromUnit].to_g, // Input in grams
inputValue * factors[fromUnit].from_g, // Input in kilograms
inputValue * factors[fromUnit].to_g * factors['mg'].from_g // Input in milligrams
];
var outputData = [
convertedValue * factors[toUnit].to_g, // Output in grams
convertedValue * factors[toUnit].from_g, // Output in kilograms
convertedValue * factors[toUnit].to_g * factors['mg'].from_g // Output in milligrams
];
// Adjust labels based on selected units for clarity
var unitLabels = {
mg: 'Milligrams (mg)',
g: 'Grams (g)',
kg: 'Kilograms (kg)',
t: 'Tonnes (t)'
};
chartLabels = [
unitLabels[fromUnit] + ' vs ' + unitLabels[toUnit] + ' (Grams)',
unitLabels[fromUnit] + ' vs ' + unitLabels[toUnit] + ' (Kilograms)',
unitLabels[fromUnit] + ' vs ' + unitLabels[toUnit] + ' (Milligrams)'
];
// Let's refine the chart data representation.
// Series 1: Value in Grams (Input) | Series 2: Value in Grams (Output)
// Series 3: Value in Kilograms (Input) | Series 4: Value in Kilograms (Output)
// This could get complex with canvas.
// Let's stick to two series representing input and output, scaled appropriately.
// We'll plot the input value and the output value on a common scale,
// represented in grams for the base comparison.
// Data for Series 1 (Input): valueInGrams, intermediateKilograms (scaled to grams), intermediateMilligrams (scaled to grams)
// Data for Series 2 (Output): convertedValue (scaled to grams), convertedValue (scaled to kg as grams), convertedValue (scaled to mg as grams)
// Let's simplify the chart to show:
// Data Series 1: The input value expressed in grams.
// Data Series 2: The converted output value expressed in grams.
// We can add more series if needed.
var chartData = {
labels: ['Value in Grams'], // Only one label for simplicity now
datasets: [
{
label: 'Input Value (' + fromUnit + ')',
data: [inputInGrams], // Display input in grams
backgroundColor: 'rgba(0, 74, 153, 0.5)', // Primary color
borderColor: 'rgba(0, 74, 153, 1)',
borderWidth: 1
},
{
label: 'Converted Value (' + toUnit + ')',
data: [outputInGrams], // Display output in grams
backgroundColor: 'rgba(40, 167, 69, 0.5)', // Success color
borderColor: 'rgba(40, 167, 69, 1)',
borderWidth: 1
}
]
};
// Add more series for Kilograms and Milligrams comparison if the scale allows
// This would require a bar chart with grouped bars or adjusting the y-axis.
// For simplicity and clarity with canvas, let's start with one comparison (in grams).
// If the user wants to see kg vs kg, mg vs mg, etc., we need separate charts or more complex datasets.
// Let's augment the datasets to include kg and mg comparisons IF the values are within a reasonable range.
// Let's re-evaluate: A good chart would compare the input and output across key units.
// Series 1: Input Value's Grams equivalent
// Series 2: Output Value's Grams equivalent
// Series 3: Input Value's Kilograms equivalent
// Series 4: Output Value's Kilograms equivalent
// This implies a chart with 4 series and potentially different y-axes or scaling.
// Canvas supports only one y-axis by default.
// Let's create a simple bar chart comparing input vs output for EACH unit (g, kg, mg).
// This means we need multiple charts or a way to cycle through them.
// Or, one chart comparing the magnitude in grams, kilograms, and milligrams.
// Let's use a single bar chart comparing input vs output for the most relevant unit,
// which is often grams or kilograms depending on the scale.
// Let's plot the input and output values in grams and kilograms side-by-side.
chartLabels = ['Grams', 'Kilograms'];
inputData = [inputInGrams, inputInGrams / 1000]; // Input in grams, Input in kg (as grams/1000)
outputData = [outputInGrams, outputInGrams / 1000]; // Output in grams, Output in kg (as grams/1000)
// Adjust labels and data based on the actual units selected for better context.
// If the user converts from mg to t, plotting both in grams might be misleading.
// Let's stick to showing the input and output in grams, and the input and output in kilograms.
// This assumes scales are not astronomically different.
chartData = {
labels: ['Value in Grams', 'Value in Kilograms'],
datasets: [
{
label: 'Input (' + fromUnit + ')',
data: [inputInGrams, inputInGrams / 1000],
backgroundColor: 'rgba(0, 74, 153, 0.6)',
borderColor: 'rgba(0, 74, 153, 1)',
borderWidth: 1
},
{
label: 'Converted (' + toUnit + ')',
data: [outputInGrams, outputInGrams / 1000],
backgroundColor: 'rgba(40, 167, 69, 0.6)',
borderColor: 'rgba(40, 167, 69, 1)',
borderWidth: 1
}
]
};
// Adjust y-axis scale if values become too large or small.
// Canvas automatically scales the y-axis.
chartInstance = new Chart(ctx, {
type: 'bar',
data: chartData,
options: {
responsive: true,
maintainAspectRatio: false,
scales: {
y: {
beginAtZero: true,
title: {
display: true,
text: 'Weight (in Grams / Kilograms)'
}
},
x: {
title: {
display: true,
text: 'Unit Scale'
}
}
},
plugins: {
title: {
display: true,
text: 'Input vs. Converted Weight Comparison'
},
legend: {
position: 'top',
}
}
}
});
}
// Initial calculation on load if default values are set
window.onload = function() {
// Set default values
document.getElementById('valueToConvert').value = '1';
document.getElementById('fromUnit').value = 'kg';
document.getElementById('toUnit').value = 'g';
calculateConversion(); // Perform initial calculation
};