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Time Calculator

A 9:00 AM to 5:00 PM day with a 30-minute unpaid break is 7.5 hours worked, which payroll systems read as 7.50 decimal hours.

Your shift

Hours worked

Total hours -
Hours : minutes -
Pay -

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The mistake that costs the most money

Almost every timesheet error traces back to one habit: treating minutes like cents. Someone works from 9:00 to 5:15, sees "15 minutes," and types 8.15 into a spreadsheet instead of 8.25. It looks close enough to be invisible and wrong enough to shortchange every paycheck it touches.

The fix: minutes divided by 60, always. Fifteen minutes is 0.25 of an hour, not 0.15.

Converting a shift by hand

Turn both clock times into minutes since midnight first. A 9:00 AM start is 540 minutes. A 5:00 PM finish is 1,020 minutes. Subtract for 480 minutes gross. Pull out a 30-minute unpaid break and you have 450 minutes left, which is 7.5 hours, or 7 hours and 30 minutes if you'd rather read it that way. Working in minutes the whole time is what keeps the clock from lying to you.

MinutesDecimal hoursHours and minutes
4507.507h 30m
4657.757h 45m
5008.338h 20m
5108.508h 30m

When the shift runs past midnight

Start at 10:00 PM, finish at 6:00 AM, and a plain subtraction gives you a negative number, because 6:00 AM looks earlier than 10:00 PM on the clock. The calculator adds 24 hours to the end time whenever this happens, which turns the math into 480 minutes, or 8 hours, before the break comes out. You never have to notice or fix this yourself; it happens automatically the moment the end time reads earlier than the start.

Turning the total into a paycheck

Payroll multiplies decimal hours by a rate, which is the whole reason decimal hours exist. A 7.5-hour shift at $16 an hour is 7.5 times $16, or $120 gross, before taxes and anything else withholding takes out. Enter a rate above to see your own figure. What this tool will not do is separate out overtime, because overtime only makes sense measured across a full workweek, not a single shift; the hours or time card calculator handles that comparison.

Things to know

Rounded punches. If your employer rounds clock-ins and clock-outs to the nearest quarter hour, the number this tool gives you from your actual times may not match your pay stub exactly. The Department of Labor allows that kind of rounding under the FLSA, as long as it is applied evenly and does not consistently work against employees over time. If yours seems to always round down, that is worth raising with payroll.

Sources: DOL Fact Sheet 22, Hours Worked under the FLSA, U.S. Department of Labor, Overtime Pay.

If this shift is part of a bigger week

Good to know

Quick answers

What's the single most common mistake people make with this kind of math?

Reading minutes as if they were cents. 8:15 gets typed as 8.15 hours when it is actually 8.25. The fix is always the same: divide the minutes by 60 before you do anything else with the number.

Why does the calculator ask for a break in minutes instead of a decimal?

Because that is how most people remember a lunch break, as 30 or 45 minutes, not as 0.5 or 0.75 of an hour. The tool does the minutes-to-decimal conversion for you internally.

My shift starts in the evening and ends after midnight. Will the total still be right?

Yes. Whenever the end time reads earlier than the start time, the calculator assumes the shift crossed midnight and adds 24 hours before subtracting, so the total comes out correct without any extra input from you.

Does a rounding policy at my job change what this tool shows?

No. This tool works from the exact times you enter. If your employer rounds punches to the nearest quarter hour, your pay stub may differ slightly from this result; the FLSA permits that kind of rounding as long as it does not consistently shortchange workers.

Can this calculator figure my weekly overtime?

No, it totals one span of time only. Overtime is a weekly calculation, so add up several shifts with the hours calculator or time card calculator to see whether you crossed 40 hours.