How we calculate

All calculations run in your browser. Times are whole minutes, totals are shown as hours and minutes (8:30) and as decimal hours (8.50), and nothing is sent to our server. The results are estimates to check your own numbers, not payroll, tax or legal advice.

Hours worked in a day

A day's hours are the end time minus the start time, minus the unpaid break minutes you enter. If the end time is earlier than the start time, the shift ends the next day and counts on the day it started.

The card flags a day instead of guessing when the start and end are the same time, when a time is missing, or when the break is as long as the shift.

Lunch punches

With lunch out and in times, a day has two work periods: In to Lunch out, and Lunch in to Out. The gap between them is the unpaid lunch. Each punch must come after the one before it; a punch that reads earlier is taken as the next day, and the four punches must fit within 24 hours.

A night shift works the same way: 10:00 PM, lunch at 2:00 AM, back at 2:30 AM and out at 6:30 AM is 8:00.

Lunch return and clock-out times

On today's row, the card shows when to come back and when to leave. Today's punches use exact minutes; earlier days use the hours shown on the card, rounded if you chose rounding:

• Back from lunch: lunch out plus 30 minutes, and plus 1 hour.
• Clock out for 8:00 today: the time you came back plus 8:00 minus the hours worked before lunch. Before lunch, it assumes a 30-minute lunch; with break minutes, it adds the minutes you entered for today.
• Clock out for the week: the weekly overtime limit, 40:00 unless you change it, minus the hours on the earlier days of the same workweek and the hours so far today. It is shown when you can reach it within the day. Before lunch, the lunch or break minutes are added only if you reach the limit after the first 4:00 of the day; if you reach it sooner, the time is for before your lunch.

The clock out calculator uses the same rules for one shift: clock-in time plus the hours to work plus the unpaid break. With lunch out and in times it uses your real lunch, and with lunch out only it counts a 30-minute lunch. A clock-out time after midnight is marked +1 day. For 40 hours, it uses the hours you type, or the days before today on this week's card saved in your browser.

Rounding

When you choose rounding, each punch is rounded to the nearest increment before the break is subtracted. Break minutes are not rounded. A punch exactly halfway rounds up.

The Rounding line in the total shows the difference from the exact punches, so you can see whether rounding evens out over time. Federal rules accept rounding to the nearest 5 minutes, tenth or quarter hour only if, over time, it does not underpay employees for the time they actually worked. Source: 29 CFR 785.48.

Weekly overtime

Hours over the weekly limit, 40 by default, are overtime. The limit is applied day by day in workweek order, so the overtime lands on the days that pass it. On a biweekly card, each week is checked on its own and the two are added. With No overtime, every hour is regular.

With the limit set to 44 hours, the same week has 1:00 of overtime. Source: DOL Fact Sheet #23.

Daily and weekly limits

With Daily and weekly limits, hours over the daily limit, 8 by default, are overtime first. The weekly limit then applies to the regular hours that are left, so no hour is counted twice.

California rules

With California rules, hours over 8 in a day are overtime and hours over 12 are double time. On the seventh consecutive workday of the workweek, the first 8 hours are overtime and the rest double time. Regular hours stop at 40 for the week. The card counts the last day of the workweek as the seventh day when all seven days have hours. Alternative workweek schedules are not modeled. Source: California Labor Commissioner.

Six days of 9:00 AM to 3:00 PM and a seventh day of 8:00 AM to 6:00 PM give 36:00 regular for the first six days, then 8:00 overtime and 2:00 double time on the seventh.

With California rules, the card also adds a note under a day that has more than 5 hours of work without a 30-minute unpaid break, a lunch that began after the fifth hour of work, or more than 10 hours of work without a second 30-minute break (with break minutes, less than 60 minutes in total). It checks the exact punches, not rounded ones. The notes are information only: the card does not add the extra hour of pay. Source: California Labor Commissioner.

Pay and the regular rate

Overtime is paid on the regular rate, not only the base wage. The card finds the regular rate as base pay for all hours plus shift differentials, divided by all hours. Regular hours are paid at that rate, overtime at 1.5 times it (or the rate you set) and double time at 2 times it. Gross pay is before taxes and deductions. Sources: 29 CFR 778.115 and 778.207.

Without a differential, 45 hours at $20 is 40 × $20 + 5 × $30 = $950.

Overtime premium

The Overtime premium line is half the regular rate for each hour over 40 in a workweek: the part of time and a half that the federal Fair Labor Standards Act requires. It is already inside gross pay, not added to it. It never shows more than the card pays above straight time, so an overtime rate under 1.5 gives a smaller amount. It appears when an overtime rule is on and the weekly limit is 40 hours or less. California daily overtime does not raise it, because only hours over 40 in the week count. In the example above, 0.5 × $20.6957 × 6 h = $62.09. The overtime calculator explains how this premium is reported on Form W-2 and the federal deduction, with IRS sources.

Night and weekend hours

Night hours are the part of each shift inside the night window, 10:00 PM to 6:00 AM unless you change it. With lunch punches, the lunch is left out exactly. With break minutes, the card does not know when the break was, so it spreads the break over the shift. Weekend hours are all the hours of shifts that start on Saturday or Sunday.

Decimal hours

Decimal hours are minutes divided by 60, shown to two places: 45:45 is 45.75 hours and 20 minutes is 0.33. Add hours and minutes first and convert the total, because rounding each line can drift. The decimal hours chart lists every minute.

Military time

Military time is the 24-hour clock without a colon. 1745 is 5:45 PM, said "seventeen forty-five," and 0005 is 12:05 AM, said "zero zero zero five." 2400 is read as midnight, 0000. See the military time converter.

Workweeks and week numbers

A workweek is a fixed period of seven consecutive days that can start on any day, so the card lets you pick the first day. The date you enter in Week of moves back to that day. When the week starts on Monday, the card shows the ISO 8601 week number (September 21, 2026 is in week 39). When it starts on Sunday, it uses the US system, where week 1 is the week with January 1 (January 4, 2026 starts week 2). Other start days show dates only. Source: 29 CFR 778.105.

What the calculators leave out

• Taxes and deductions. The card shows the overtime premium, not the tax deduction you may claim.
• State overtime rules other than California, and California alternative workweek schedules.
• Meal and rest break premium pay (the California meal notes are information only), split shift pay and on-call time.
• Salaried overtime methods such as the fluctuating workweek.
• More than two work periods in one day.

Report an error

If a result looks wrong, email contact@timecardkit.com with the page, the times and settings you used, and what you expected. A Share link from the card carries all of that. We check every report, fix confirmed errors and update the date on the page.