What a time card includes
A standard hourly time card has at least these fields per day: clock-in, clock-out, total hours, and (if applicable) lunch start and lunch end. A weekly or biweekly version adds totals per workweek.
Step-by-step
- 1
Calculate gross daily hours
End time − Start time. For 8:00 AM to 5:30 PM, that is 9h 30m. - 2
Subtract unpaid breaks
30-minute unpaid lunch → 9h 30m − 30m = 9h 00m paid that day. - 3
Convert to decimal
9h 0m = 9.00 decimal hours. 7h 45m would be 7.75. - 4
Sum each workweek
Add daily decimals to get the weekly total. For biweekly pay, do this for each week separately. - 5
Apply overtime per workweek
Hours over 40 in a workweek are paid at 1.5× the regular rate (federal FLSA rule). - 6
Multiply by hourly rate
Regular hours × rate, plus overtime hours × (rate × 1.5), gives gross pay.
Worked example: a one-week time card
| Day | Clock in | Clock out | Lunch (min) | Paid hours | Decimal |
|---|---|---|---|---|---|
| Mon | 8:00 AM | 5:00 PM | 30 | 8h 30m | 8.50 |
| Tue | 7:45 AM | 4:45 PM | 30 | 8h 30m | 8.50 |
| Wed | 8:00 AM | 5:15 PM | 30 | 8h 45m | 8.75 |
| Thu | 8:00 AM | 6:00 PM | 30 | 9h 30m | 9.50 |
| Fri | 8:00 AM | 4:00 PM | 30 | 7h 30m | 7.50 |
| Total | 42h 45m | 42.75 |
40 regular hours + 2.75 overtime hours. At $25/hour: 40 × $25 = $1,000 + 2.75 × $37.50 = $103.13. Estimated gross pay: $1,103.13.
Common time card mistakes
- Adding hours and minutes as decimals. 7h 45m is 7.75, not 7.45.
- Auto-deducting lunch when it was not taken. Pay the actual time worked.
- Mixing AM and PM clock times. Convert to 24-hour or be explicit before subtracting.
- Calculating overtime per pay period. Overtime is per workweek, even on biweekly schedules.
Building a clean weekly time card
A defensible time card shows clock-in, clock-out, unpaid break minutes, and net paid time per day. The weekly total appears at the bottom along with regular and overtime splits. If you build a time card by hand or in a spreadsheet, follow the same column order so anyone can audit it: date, clock-in, clock-out, break, net, and a notes column for exceptions like working through lunch.
Spreadsheet approach
In a spreadsheet, store clock-in and clock-out as actual time values. Compute net paid minutes with (clock-out minus clock-in) times 1440 minus break minutes. Convert net minutes to decimal hours by dividing by 60. Sum the decimal column for the week. This avoids the most common bug, which is treating the time difference as a date and getting the wrong day's value.
Handling overnight shifts
Overnight shifts make the math trickier because clock-out is after midnight. The fix is to add 24 hours to the clock-out when it is earlier than the clock-in. Most calculators including the Shift Hours Calculator have an "overnight" toggle that handles this automatically. If you build your own logic, test it explicitly with a 11:00 PM in / 7:00 AM out shift and confirm the total reads 8 hours, not negative 16.
When AM and PM look the same
One of the most common time card errors is recording 12:00 PM as 12:00 AM or vice versa. Noon and midnight are confusing because both are technically 12 o'clock. The clean fix is to convert everything to 24-hour time before subtraction. Noon is 12:00, midnight is 00:00 (or 24:00 at the end of the day). Run a quick sanity check: morning shifts should produce positive net hours under 12 unless the employee really did work all day.
Important note
Time card rules and rounding policies vary by employer, state, and union contract. Always confirm calculations with your employer or payroll provider before submitting payroll.