Work Hours Calculator

Subtract the start from the end, then take off the break. From 9:00 AM to 5:30 PM is 8 hours 30 minutes; with a 30-minute unpaid break, that leaves 8:00 on the card. The calculator reports the same shift three ways: as hours and minutes (8:00), as decimal hours (8.00) and as total minutes (480). Each has its place — the clock reading is what you say out loud, the decimal is what payroll wants, and the minute count is what settles an argument about a late clock-in.

This is where timesheets quietly leak money. 8 hours 30 minutes is 8.5 hours, not 8.30. The clock runs in base 60 and the decimal runs in base 10, so the minutes have to be divided by 60 — you cannot simply move them behind a decimal point. The conversions worth memorizing: 15 minutes is 0.25, 20 minutes is 0.33, 30 minutes is 0.5, 40 minutes is 0.67, 45 minutes is 0.75. Going the other way, multiply the fraction by 60: 1.5 hours is 1h30, never 1h50. The error is small per day and large per year. Writing 8.30 where you worked 8:30 gives away 12 minutes a shift; across 250 working days that is 50 hours, more than a full week of unpaid work.

A shift from 10:00 PM to 6:00 AM has an end time numerically smaller than its start, so a plain subtraction returns minus 16 hours. The calculator detects the negative result and adds 24 hours, giving the correct 8 hours. One consequence is worth knowing: an overnight shift belongs to two calendar dates. Employers differ on whether those hours are credited to the day the shift started or the day it ended, and that choice can move hours between two pay periods or across a workweek boundary. Ask which convention yours uses before trying to reconcile a disputed week.

A genuine meal break — long enough that you are relieved of duty — is typically unpaid, which is why it is subtracted here. Short rest breaks are a different matter: under the federal Fair Labor Standards Act, brief rest periods are generally counted as hours worked and paid. If your breaks are the short kind, set the break field to 0 instead of deducting them. Time spent working through a meal is also hours worked, even when the schedule calls it a break. Eating at your desk while answering the phone is not a relieved-of-duty break, so that time belongs on the card.

Many employers round clock punches to the nearest quarter hour. Rounding is not automatically improper — what matters is that it works neutrally over time, cutting both ways rather than always in one direction. This calculator handles a single shift. Overtime under the FLSA, by contrast, is a weekly question: it turns on hours worked in a workweek, not on any one long day. Add up your shifts across the week before deciding whether any hours qualify, and check your state as well, since some states set daily overtime thresholds on top of the federal weekly rule. Shift differentials, on-call pay, paid time off and holiday premiums are employer policy and sit outside this calculation entirely.