Everyday calculator

Free hours calculator

Enter a start and end time — this hours calculator returns the total hours worked in both decimal and hours:minutes format, including overnight shifts, updated live, as you type.

InputsLive
Clock in
Clock out
Break time
min
Result
Net hours worked
8 hr
Total: 8.5 hr · Break: 30 min
Net hours8
Total hours8.5
Clock in09:00
Clock out17:30

Net hours = clock-out − clock-in − break time.

Results are estimates. Consult a professional.

How it's calculated

How the hours calculator works

Enter a start time and an end time and the calculator returns the difference in decimal hours, in hours and minutes, or both. It handles overnight shifts automatically — if the end time is earlier than the start time, the calculator adds 24 hours to account for the shift crossing midnight. This is the standard method used in payroll and timesheet software.

hours between = (end time start time) in minutes ÷ 60
overnight fix = if end < start, add 24 hours to end time first
decimal hours = hours + (minutes ÷ 60)
example = 7 h 30 min = 7 + (30 ÷ 60) = 7.50 decimal hours
US Department of Labor — Fair Labor Standards Act (FLSA): converting hours and minutes for payroll calculations.
Example

Worked example: overnight shift 10 PM to 6 AM

Example: overnight shift from 10:00 PM to 6:00 AM

A nurse works an overnight shift starting at 10:00 PM and finishing at 6:00 AM the following morning. The end time is earlier than the start time, so the calculator adds 24 hours to the end.

adjusted end time = 6:00 AM + 24 h = 30:00 (i.e. 6 AM next day)
hours worked = 30:00 22:00 = 8 hours
decimal hours = 8.00
8 hours / 8.00 decimal
An overnight shift from 10 PM to 6 AM is exactly 8 hours, or 8.00 in decimal format for payroll entry.
Quick reference

Minutes to decimal hours conversion table

Payroll systems almost always require decimal hours. Use this table to convert the minutes portion of any shift quickly.

MinutesDecimal fraction
00.00
150.25
200.33
300.50
400.67
450.75

Source: US DOL FLSA timesheet guidance. Add the decimal fraction to the whole hours to get the payroll entry (e.g. 7 h 45 min = 7.75).

Practical tips

Tips for calculating work hours

Accurate hour tracking protects both employees and employers. These tips cover the most common sources of error.

  • Always use decimal hours for payroll — most payroll software multiplies the decimal figure by the hourly rate. Entering 7:30 as 7.30 (not 7.50) will under-pay by 20 minutes worth of wages.
  • Account for unpaid breaks — if an employee takes a 30-minute unpaid lunch, calculate the morning and afternoon blocks separately and add them, rather than subtracting from the full shift duration.
  • Check overnight shifts twice — an 8-hour shift on a 12-hour clock that goes from 9 PM to 5 AM looks like 4 hours at first glance. The calculator handles this automatically when you enter the correct AM/PM.
  • Round consistently — the FLSA allows rounding to the nearest 5 or 15 minutes, but the rounding must be neutral across employees. Confirm your employer's rounding policy before applying it.
  • Sum daily totals before multiplying — add all daily hour totals for the week first, then multiply by the hourly rate. Rounding each day individually can introduce small cumulative errors.
Accuracy & limits

Accuracy and limitations

The hours calculator is exact to the minute for any same-day or overnight shift up to 24 hours. It uses 12-hour or 24-hour clock input and converts internally to minutes before dividing, so there are no rounding errors within a single shift calculation.

The calculator does not handle multi-day shifts longer than 24 hours, nor does it calculate overtime thresholds, holiday pay, or premium rates — those depend on your jurisdiction and employment contract. For weekly totals or payroll processing, enter each shift separately and add the results.

Glossary

Hours calculator terms defined

Hours expressed as a single number with a decimal fraction rather than hours and minutes. Used in payroll: 7 h 30 min = 7.50 decimal hours.
A work period that starts on one calendar day and ends on the next. The calculator adds 24 hours to the end time to give the correct duration.
Fair Labor Standards Act — US federal law that sets minimum wage, overtime pay, and recordkeeping requirements, including timesheet calculation methods.
A record of start and end times for each work period. The calculated hours are multiplied by the hourly rate to determine gross pay.
Unpaid time subtracted from the total shift duration. Must be calculated separately from the paid-hours total.
About

About this hours calculator

This calculator runs entirely in your browser — nothing you enter is sent to any server.

Browse more in our everyday calculators, or explore the complete library on the free calculators page.

Questions

Frequently asked questions about the free hours calculator

A hours calculator is a free online tool that helps you calculate total hours between two times. Same as time duration. It runs entirely in your browser with instant results and no sign-up.
These calculators use the local browser timezone. For UTC-based work, plan accordingly.
Some calculators round differently (Naegele's rule uses 280 days, but some use 'last menstrual period + 38 weeks' giving slightly different results). Different inputs (calendar conventions) also matter.

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