Calculator to Calculate Hours

Professional Hours Calculator

Calculate total work time, including overnight shifts and breaks.

12123 4567 891011 00153045 AM PM
12123 4567 891011 00153045 AM PM

Calculation Result

0 Hours 0 Minutes
Decimal: 0.00 hours

How to Use the Hours Calculator

This hours calculator is designed for employees, freelancers, and project managers who need to track precise working durations. It simplifies the process of subtracting start times from end times while accounting for unpaid breaks and overnight shifts.

Step-by-Step Instructions

  1. Enter Start Time: Select the hour, minute, and AM/PM designation for when your shift or task began.
  2. Enter End Time: Select the time you finished. The calculator automatically handles shifts that cross midnight (e.g., starting at 10:00 PM and ending at 6:00 AM).
  3. Deduct Breaks: Enter the total number of minutes taken for lunch or other unpaid breaks.
  4. Review Results: The tool provides two outputs: standard "Hours and Minutes" for easy reading, and "Decimal Hours" for payroll software and billing calculations.

Example Calculations

  • Standard Shift: 9:00 AM to 5:00 PM with a 60-minute break = 7 hours 0 minutes (7.00 decimal)
  • Overtime Shift: 8:30 AM to 6:45 PM with a 45-minute break = 9 hours 30 minutes (9.50 decimal)
  • Night Shift: 10:00 PM to 6:00 AM with no break = 8 hours 0 minutes (8.00 decimal)

Why Use Decimal Hours?

Most payroll systems require time to be entered in decimal format. For example, if you work 8 hours and 15 minutes, you cannot simply write "8.15" for payroll because 15 minutes is 25% of an hour. This calculator correctly converts 8 hours and 15 minutes into 8.25 decimal hours, ensuring you are paid accurately for every minute worked.

Common Minute-to-Decimal Conversions

Minutes Decimal Equivalent
15 Minutes0.25
30 Minutes0.50
45 Minutes0.75
function calculateHours() { // Get raw values var startH = parseInt(document.getElementById("startHour").value); var startM = parseInt(document.getElementById("startMin").value); var startAP = document.getElementById("startAmPm").value; var endH = parseInt(document.getElementById("endHour").value); var endM = parseInt(document.getElementById("endMin").value); var endAP = document.getElementById("endAmPm").value; var breakTime = parseInt(document.getElementById("breakMinutes").value) || 0; // Convert Start Time to 24hr minutes if (startAP === "PM" && startH !== 12) startH += 12; if (startAP === "AM" && startH === 12) startH = 0; var startTotalMinutes = (startH * 60) + startM; // Convert End Time to 24hr minutes if (endAP === "PM" && endH !== 12) endH += 12; if (endAP === "AM" && endH === 12) endH = 0; var endTotalMinutes = (endH * 60) + endM; // Handle overnight shifts if (endTotalMinutes <= startTotalMinutes) { endTotalMinutes += (24 * 60); } // Calculate duration var durationMinutes = endTotalMinutes – startTotalMinutes – breakTime; if (durationMinutes < 0) { durationMinutes = 0; } // Convert back to display units var finalHours = Math.floor(durationMinutes / 60); var finalMins = durationMinutes % 60; var decimalHours = (durationMinutes / 60).toFixed(2); // Update UI document.getElementById("totalHoursText").innerText = finalHours + " Hours " + finalMins + " Minutes"; document.getElementById("decimalHoursText").innerText = "Decimal: " + decimalHours + " hours"; document.getElementById("resultArea").style.display = "block"; }

Leave a Comment