Hourly Time Calculator

by

Hourly Time Calculator

Calculation Summary

Total Time:

Decimal Format: hours

What is an Hourly Time Calculator?

An hourly time calculator is an essential tool for employees, freelancers, and project managers to accurately track duration between two specific times. Whether you are filling out a weekly timesheet, tracking billable hours for a client, or calculating the length of a travel journey, this tool simplifies the math involved in temporal calculations.

How to Calculate Hours and Minutes

Calculating the difference between a start and end time manually can be tricky because time is based on a 60-minute system rather than a decimal system. To calculate manually, follow these steps:

  1. Convert both the start and end times into "minutes since midnight". (Hours × 60 + Minutes).
  2. Subtract the start minutes from the end minutes.
  3. If the end time is on the next day (e.g., 10:00 PM to 2:00 AM), add 1,440 minutes (24 hours) to the end time before subtracting.
  4. Subtract any unpaid break time (in minutes).
  5. Divide the final result by 60 to get the decimal hours, or convert it back into hours and minutes.

Real-World Example

Imagine you start your work shift at 08:30 AM and finish at 05:15 PM, with a 45-minute lunch break.

  • Start Time: 8:30 = (8 × 60) + 30 = 510 minutes.
  • End Time: 17:15 = (17 × 60) + 15 = 1035 minutes.
  • Gross Duration: 1035 – 510 = 525 minutes.
  • Net Duration: 525 – 45 (break) = 480 minutes.
  • Final Result: 480 / 60 = 8.0 hours.

Decimal Hours vs. Time Format

In payroll systems, you often need decimal hours. For example, 7 hours and 30 minutes is 7.5 hours. Many people make the mistake of writing 7:30 as 7.3, which can lead to significant underpayment or overpayment errors. Our calculator provides both formats to ensure your records are 100% accurate for payroll processing.

function calculateHours() { var startTimeStr = document.getElementById("startTime").value; var endTimeStr = document.getElementById("endTime").value; var breakMin = parseFloat(document.getElementById("breakDuration").value); if (!startTimeStr || !endTimeStr) { alert("Please select both start and end times."); return; } if (isNaN(breakMin)) { breakMin = 0; } var startParts = startTimeStr.split(":"); var endParts = endTimeStr.split(":"); var startMinutes = (parseInt(startParts[0]) * 60) + parseInt(startParts[1]); var endMinutes = (parseInt(endParts[0]) * 60) + parseInt(endParts[1]); // Handle overnight shifts if (endMinutes < startMinutes) { endMinutes += 1440; // Add 24 hours in minutes } var totalMinutes = endMinutes – startMinutes; var netMinutes = totalMinutes – breakMin; if (netMinutes < 0) { alert("Break duration cannot be longer than the shift duration."); return; } var finalHours = Math.floor(netMinutes / 60); var finalRemainingMinutes = Math.round(netMinutes % 60); var decimalValue = (netMinutes / 60).toFixed(2); document.getElementById("totalTimeString").innerText = finalHours + " hours and " + finalRemainingMinutes + " minutes"; document.getElementById("decimalHours").innerText = decimalValue; document.getElementById("resultArea").style.display = "block"; }

Leave a Comment