Time Card Calculator
Convert hours and minutes into decimal hours across a week, deduct breaks, split regular from overtime, and see what a rounding policy actually costs.
Deducted from every day entered.
8 hours 15 minutes is 8.25 hours, not 8.15. Minutes are sixtieths, and treating them as hundredths is the single most common payroll arithmetic error.
What this calculator does
Five days of hours and minutes, an unpaid break, an hourly rate, an overtime threshold and a rounding increment go in. It returns each day in decimal hours, the exact weekly total, the rounded total, regular and overtime hours split, regular and overtime pay, gross pay, and how much the rounding policy moved the week.
That last figure is the reason to use this rather than a payroll app, because it is the one nobody shows you.
Minutes are sixtieths
This is the error the page exists for.
8 hours 15 minutes is 8.25 hours. Not 8.15.
It happens because minutes look like decimals — both are the small number after the big one — and they are not. Minutes are sixtieths. Fifteen out of sixty is 0.25.
Written as 8.15, that day is short by six minutes. Across a five-day week with similar entries, close to half an hour. Across a year, more than a full working week of unpaid time.
The awkward conversions worth knowing:
| 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 the quarter-hours come out clean. Everything else repeats, which is precisely why quarter-hour policies exist at all.
Rounding, and why the delta line matters
Rounding to a small increment — most often the quarter hour — is a long-standing payroll practice, and where the policy is neutral it is generally permitted.
Neutral means it rounds both directions. Seven minutes past the quarter rounds down; eight rounds up. Over weeks it averages out to approximately nothing.
A policy that only ever rounds down is not a rounding policy. It is a small, systematic reduction in hours paid, and it is a wage issue rather than a bookkeeping one. The same is true of rounding clock-in up and clock-out down — technically two roundings, both in the same direction.
The calculator shows the rounding delta explicitly so you can see which way it went this week. One week proves nothing; a pattern across many weeks does.
Rules vary by jurisdiction, and some are stricter than others. If a policy is consistently costing you time, that is worth raising with the state labour agency rather than resolving with arithmetic.
Breaks
The general principle: a genuine break where you are relieved of duty is unpaid; a short rest break is paid.
Where this goes wrong in practice is not the rule but the reality. Time spent working through a break counts as time worked, regardless of what the schedule says. Eating at your desk while answering the phone is not an uninterrupted break. Being on call and required to stay on premises is frequently compensable.
The deduction in this calculator applies to every day entered, which is how most schedules work. If your breaks vary, adjust the daily minutes instead.
Overtime is more complicated than one threshold
The calculator uses a single weekly threshold and a multiplier, which covers the standard case and not every case.
Weekly overtime past forty hours at one and a half times the regular rate is the baseline federal rule in the US.
Daily overtime exists in several states — hours past eight in a single day attract overtime whether or not the week exceeds forty. Which means an identical timecard produces different pay in different states, and a week of four ten-hour days is straight time federally and partly overtime in a daily-overtime state.
The regular rate is not always the hourly rate. Non-discretionary bonuses, shift differentials and commissions generally have to be folded into the regular rate before the overtime multiplier is applied — which raises the overtime rate above 1.5 times the base wage.
Exempt employees are not entitled to overtime at all, and classification turns on duties and salary rather than on job title.
The overtime pay calculator works from maintained state-by-state rules and handles the daily-overtime states properly. This one does arithmetic on a threshold you supply.
Keep your own record
The practical advice underneath all of this.
If your hours are tracked by someone else’s system, keep a parallel record. A note on your phone with in and out times takes fifteen seconds a day.
It matters for a specific reason: in most wage disputes, where the employer’s records are incomplete or inaccurate, an employee’s own contemporaneous record carries real weight. Reconstructing hours from memory a year later does not.
Nobody expects to need this. The people who did need it universally wish they had started earlier.
What this leaves out
- Daily overtime rules, covered by the overtime pay calculator.
- Regular rate calculation including bonuses and differentials.
- Double time, required in some states past a daily hour count.
- Seventh-consecutive-day premium rules.
- Taxes and deductions. This is gross pay — the hourly paycheck calculator covers what lands in the account.
- Exempt classification, which is a duties test rather than a calculation.
- Multiple pay rates in one week.
For estimating labour on a job rather than recording it, the crew hours calculator works from production rates.
How this is calculated
decimal hours = hours + minutes ÷ 60 − break ÷ 60 8 hr 15 min = 8.25 hrs NOT 8.15 regular = min(week total, overtime threshold) overtime = max(0, week total − threshold) × multiplier
Frequently asked questions
- How do I convert minutes to decimal hours?
- Divide the minutes by 60. Fifteen minutes is 0.25 hours, thirty is 0.5, forty-five is 0.75. Writing 8 hours 15 minutes as 8.15 instead of 8.25 is the most common payroll arithmetic error there is, and it consistently underpays by six minutes a day.
- What is 7 hours and 40 minutes in decimal?
- 7.67 hours — forty divided by sixty is 0.667. The awkward ones are worth knowing — 10 minutes is 0.17, 20 is 0.33, 40 is 0.67, 50 is 0.83. Everything that is not a quarter-hour produces a repeating decimal, which is exactly why quarter-hour rounding policies exist.
- Can an employer round time card hours?
- Rounding to a small increment is generally permitted where the policy is neutral — rounding both up and down so it averages out over time. A policy that only ever rounds against the employee is a wage problem rather than a bookkeeping one. Rules vary by jurisdiction, so check yours.
- How is weekly overtime calculated?
- Hours beyond the weekly threshold, most commonly forty, are paid at a multiplier of the regular rate — usually one and a half. Some states additionally require daily overtime past eight hours in a single day regardless of the weekly total, which means the same timecard can produce different overtime in different states.
- Do unpaid breaks count toward hours worked?
- A genuine, uninterrupted meal break where you are relieved of duty is generally unpaid and does not count. Short rest breaks are typically paid and do count. Time spent working through a supposed break counts as work, whatever the schedule says — which is where most break-related wage disputes originate.