The time desk
Free Online Hours Calculator
Enter a start time and an end time, subtract your break, and see exactly how many hours you worked — as h:mm, as decimal hours and as minutes. Overnight shifts are handled automatically.
THE ARITHMETIC
How the hours calculator works
Every clock time is first converted into one number: minutes elapsed since midnight. 8:00 AM becomes 480. 4:45 PM becomes 1005. Once both ends of the shift are plain integers, the rest is subtraction — and subtraction of integers never produces the rounding artefacts you get from subtracting decimals.
The complete formula, in the order the calculator applies it:
end minutes − start minutes (+1440 if negative) − unpaid break = net minutes
net minutes → h:mm by dividing by 60 with remainder; decimal hours = net minutes ÷ 60, rounded to 2 places
The +1440 step is what handles a shift that ends on the following calendar day: 1440 is the number of minutes in 24 hours, so adding it once converts a negative result into the real elapsed time. The break is deducted last, after the span is known, because an unpaid meal period sits inside the shift rather than extending it.
Gross pay, when you enter an hourly rate, is calculated from the decimal hours: rate × decimal hours. That ordering matters. Payroll systems pay on decimal hours, so quoting pay from the rounded decimal figure is what matches the number that eventually lands on a pay stub.
REAL NUMBERS
Three worked shifts
A standard office day with an unpaid lunch
In at 8:00 AM, out at 4:45 PM, 30 unpaid minutes for lunch.
1005 − 480 = 525 min − 30 = 495 min = 8:15 = 8.25 decimal hours
At $24.00 an hour that is $198.00 gross for the day. Note that 8:15 is not 8.15 hours; fifteen minutes is a quarter of an hour, so the decimal figure is 8.25. Writing 8.15 on a timesheet gives away six minutes of pay per day, which compounds to roughly two and a half hours over a year of five-day weeks.
A night shift that crosses midnight
In at 10:30 PM, out at 6:15 AM, 45 unpaid minutes for a meal break.
375 − 1350 = −975 → −975 + 1440 = 465 min − 45 = 420 min = 7:00 = 7.00 hours
Because the end time is earlier on the clock than the start time, the calculator treats the shift as crossing midnight automatically — there is no checkbox to remember. If you genuinely need a span longer than 24 hours, split it into two entries, one per calendar day, which is also how payroll wants it recorded.
A short retail shift with no break
In at 10:15 AM, out at 2:50 PM, no break deducted, rate $17.50.
890 − 615 = 275 min = 4:35 = 4.58 hours × $17.50 = $80.15
275 minutes divided by 60 is 4.58333…, which the calculator shows as 4.58. That third decimal place is where penny-level differences between you and your employer's system come from; see the rounding note further down before you raise a discrepancy over eight cents.
CONVERSION TABLE
Minutes as decimal hours
Payroll runs on hundredths of an hour, not on minutes. These are the values that come up most often; the hours to decimal converter handles any value in between, and the full minute-by-minute table covers all 60.
| Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|
| 5 | 0.08 | 35 | 0.58 |
| 10 | 0.17 | 40 | 0.67 |
| 15 | 0.25 | 45 | 0.75 |
| 20 | 0.33 | 50 | 0.83 |
| 25 | 0.42 | 55 | 0.92 |
| 30 | 0.50 | 60 | 1.00 |
Only quarter hours convert to tidy two-decimal values. Twenty minutes is 0.3333 recurring and fifty minutes is 0.8333 recurring, so both are shown rounded. Over a full week those roundings offset each other rather than accumulating, because each day is rounded independently from its own exact minute count.
INPUT FORMATS
What you can type into the time fields
Typing is faster than tapping a dropdown, so the fields accept the shorthand people actually use. All of these parse to the same instant: 9, 930, 0930, 9:30, 9.30, 9:30 AM. Evening times accept 9:30pm or the 24-hour form 21:30.
The 12h/24h toggle changes only how results and the breakdown sentence are displayed — it does not restrict what you may type. Switch it to 24-hour if you work in a hospital, a transport operation, or anywhere outside the United States where the AM/PM clock is the unusual one.
If a break is longer than the shift itself, the calculator refuses the entry and shows an error rather than a negative total. A negative number of hours worked is always a typo, and silently displaying one is how bad figures reach a pay run.
PAY RULES
Breaks, overtime and the limits of arithmetic
Enter only the break time you are not paid for. Under federal rules a genuine meal period during which you are relieved of duty is generally unpaid, while short rest breaks of roughly five to twenty minutes are typically counted as hours worked and paid. If you answer the phone or cover the counter through lunch, that period may well be compensable — our guide on paid and unpaid break time goes through the distinctions.
Overtime under the federal Fair Labor Standards Act is 1.5× the regular rate for hours over 40 in a workweek. A handful of states add daily overtime, typically after 8 hours in a day, and some add a double-time tier; thresholds and exemptions differ by state and by industry, and outside the US the rules are different again. For a whole week with both thresholds applied, use the overtime calculator or the seven-day time card calculator instead of adding single shifts by hand.
This tool does arithmetic on the numbers you give it. It is not legal or payroll advice, and it cannot know your state, your union agreement or your employer's rounding policy.
PICK THE RIGHT TOOL
One shift, one week, or one conversion
This page answers a single question well: how long was this shift, and what is it worth. Once you need more than one day at a time, a different layout saves effort.
| What you have | Use |
|---|---|
| One shift, with or without a break | This page |
| Seven days of punches with overtime | Time card calculator |
| A week to submit for approval | Timesheet calculator |
| Two times, no break or pay involved | Time duration calculator |
| Hours and minutes to convert | Hours to decimal |
| A finish time to work forward to | Add time calculator |
If you are checking your own pay rather than running a schedule, the work time calculator covers the same single-shift arithmetic with guidance on reconciling against a pay stub. Beginners who want the method step by step should start with the walkthrough on calculating hours worked, which builds up the same formula from scratch with a worked week at the end.
WHERE IT GOES WRONG
Four mistakes that change someone's paycheck
Reading h:mm as a decimal
The single most expensive error in manual time calculation. 7:45 is 7.75 hours. 7:20 is 7.33 hours. A timesheet full of h:mm values typed straight into a decimal-hours field understates most shifts and overstates a few.
Rounding every day before adding the week
Round at the end, not at each step. Seven days each rounded to two decimals can drift from the true weekly total by a couple of minutes — enough to move you either side of the 40-hour overtime line.
Deducting an automatic break that was never taken
Many clock systems subtract 30 minutes whether or not you clocked out. If you worked through, the deduction is wrong and you should flag it in writing the same week rather than at the end of the quarter.
Flipping AM and PM
8:00 PM to 4:45 AM is a legitimate overnight shift, but so is 8:00 AM to 4:45 PM, and the two differ by exactly one letter. The breakdown sentence under the result restates the shift in words for exactly this reason: read it back before you copy the figure anywhere.
ACCURACY
How we verify the numbers
All parsing and arithmetic happens in whole minutes as integers. Decimal hours appear only at the final step, rounded to two places, so repeated additions cannot accumulate floating-point drift the way a chain of spreadsheet formulas can. The formulas are covered by 50 automated unit tests that run on every change to the code, including the awkward cases: midnight-to-midnight, a shift ending exactly at the start time, a break equal to the shift length, and single-digit input like 9.
Nothing you type is transmitted. The calculation runs entirely in your browser, with no network request, no account and no server-side copy of your hours or your wage. The full method, including how overtime is split and how the weekly grid stores a week locally, is written up on how this calculator works. If you find a case where our figure and your employer's disagree and you believe ours is wrong, tell us — we would rather fix the tool than defend it.
Frequently asked questions
Common questions
How do I calculate hours worked with a lunch break?
Work out the full span from clock-in to clock-out first, then subtract the unpaid break from that total. A shift from 8:00 AM to 4:45 PM is 8 hours 45 minutes; take off a 30-minute unpaid lunch and you are left with 8 hours 15 minutes, or 8.25 decimal hours.
Only deduct break time you are not paid for. Short rest breaks of roughly five to twenty minutes are generally treated as hours worked under federal rules, while a genuine meal period where you are relieved of all duty is normally unpaid.
What is 7 hours and 45 minutes in decimal hours?
7 hours 45 minutes is 7.75 decimal hours. Divide the minutes by 60 rather than writing them after the decimal point: 45 ÷ 60 = 0.75. The common mistake is entering 7.45, which understates the shift by 18 minutes.
Not every value is tidy. 7 hours 20 minutes is 7.3333 recurring, shown as 7.33 when rounded to two decimal places, which is the precision payroll systems normally use.
How do I calculate hours for a shift that crosses midnight?
Subtract as normal, and if the answer is negative add 24 hours (1440 minutes) once. A shift from 10:30 PM to 6:15 AM gives 6:15 − 22:30 = −975 minutes; adding 1440 gives 465 minutes, which is 7 hours 45 minutes before any break deduction.
This calculator applies that step automatically whenever the end time falls earlier on the clock than the start time, so there is nothing extra to tick. For spans longer than 24 hours, enter each calendar day separately.
Is this hours calculator free and do I need an account?
It is free with no sign-up, no trial and no usage limit. There is no account to create because there is nothing stored on our side: the arithmetic runs inside your own browser, with no network request sent when you press calculate.
That also means your start times, end times and hourly rate never leave your device. The site is supported by advertising, not by selling or processing your data.
How many hours is 9 to 5 with an hour for lunch?
9:00 AM to 5:00 PM is an 8-hour span. Deduct a one-hour unpaid lunch and you have 7 hours of paid time, or 7.00 decimal hours. That is why a nominal "9 to 5" job with a full unpaid lunch hour is a 35-hour week rather than a 40-hour one.
With a 30-minute lunch instead, the same span pays 7 hours 30 minutes, or 7.50 decimal hours, which works out to 37.5 hours across five days.
When does overtime start in the US?
Under the federal Fair Labor Standards Act, non-exempt employees are owed 1.5 times their regular rate for hours worked over 40 in a workweek. The workweek is a fixed, recurring 168-hour period that your employer defines; hours do not average across two weeks.
Some states add daily overtime, commonly after 8 hours in a day, and a few add a double-time tier. Thresholds, exemptions and industry carve-outs vary by state, and rules outside the United States differ entirely.
What time formats can I type into the calculator?
You can type 9, 930, 0930, 9:30, 9.30 or 9:30 AM and they all parse to half past nine in the morning. Evening times accept 9:30pm or the 24-hour form 21:30.
The 12h/24h toggle changes how results are displayed but never restricts what you may type, so you can paste values straight from a punch clock report without reformatting them first.
Why does my total differ from my employer's time clock?
Usually one of three reasons: rounding, an automatic break deduction, or a different workweek boundary. Many clock systems round punches to the nearest quarter hour, so a 7:58 AM punch may be recorded as 8:00 AM. Others subtract a fixed 30-minute meal whether or not you clocked out for it.
Compare the raw punch times on your own record against the hours the stub pays, day by day, and raise any gap in writing while the pay period is recent. A one-minute difference is rounding; a recurring 30-minute difference is a policy worth questioning.
Can I calculate my gross pay as well as my hours?
Yes. Enter an hourly rate and the calculator multiplies it by the decimal hours, so a 8.25-hour day at $24.00 an hour shows $198.00. It deliberately uses the rounded decimal figure because that is the number payroll systems pay on.
The result is gross pay before any deduction. It does not model taxes, Social Security, Medicare, benefit contributions, shift differentials or overtime premiums, so treat it as a check on the hours rather than a prediction of your net paycheck.
Does the calculator work on a phone and without internet?
Yes to both. The layout is built for a phone keypad first, and because all the arithmetic is local JavaScript, the page keeps calculating once it has loaded even if your connection drops — useful on a job site or a loading dock.
You can copy the result to the clipboard, share it, or print the page as a record. Nothing is uploaded when you do.
For bloggers and HR teams
Embed this calculator on your own site
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Last reviewed 1 November 2026 by the Hours Calculator Online team. Spotted a problem? Tell us and we will fix it.