How to Read a Weekly Time Card: Breaks, Overnight Shifts, and Overtime Explained
By the Super Simple Digital Tools Team · Updated June 2026
A time card looks simple, but the small details are where pay quietly leaks away. The core skill is converting clock times into a duration: count the whole hours between start and finish, then handle the leftover minutes separately. A shift from 8:15 AM to 4:45 PM is 8 hours and 30 minutes, or 8.5 hours in decimal. Payroll systems run on decimal hours, so getting comfortable converting minutes to decimals (15 minutes is 0.25, 30 is 0.5, 45 is 0.75) is the single most useful habit when checking your own card.
Breaks are the next sticking point. Unpaid meal breaks must be subtracted from the shift, while short paid rest breaks usually count as worked time. If you take a 45-minute lunch, that time comes off the total before any overtime is figured. Be consistent about whether a break is paid or unpaid across the week, because mixing the two is one of the most common reasons a hand-totaled card disagrees with the final paycheck.
Overnight shifts cause more confusion than any other case because the clock numbers go down instead of up. A shift that starts at 9:00 PM and ends at 5:00 AM cannot be calculated by subtracting 9 from 5. The trick is to add 24 hours to the end time: 5:00 AM becomes 29:00, and 29 minus 21 (9:00 PM) gives 8 hours. A calculator handles this automatically by detecting that the end time is not later than the start time, but it helps to understand the logic so you can sanity-check the result.
Rounding is where compliance enters the picture. Many employers round clock punches to the nearest quarter hour using the 7-minute rule: punches 1 to 7 minutes past a quarter mark round down, and 8 to 14 minutes round up. The FLSA permits this only if it stays neutral over time. If your start punches keep rounding against you and your end punches do too, the rounding is favoring the employer, which is not allowed. Comparing your raw punches against the rounded total occasionally is a good way to catch a pattern.
Finally, separate overtime before you celebrate a big total. Federal rules pay time and a half for hours past 40 in a workweek, and some states add daily overtime past 8 hours. A week of five 9-hour days is 45 hours: 40 at the regular rate and 5 at one and a half. Splitting regular and overtime hours, rather than lumping everything together, is what makes your estimate match what payroll actually pays.
- Convert minutes to decimals when checking pay: 15 minutes is 0.25, 30 is 0.5, and 45 is 0.75 of an hour.
- For overnight shifts, mentally add 24 hours to the end time before subtracting, or let the calculator detect the midnight crossing for you.
- Decide up front whether each break is paid or unpaid and apply it the same way every day so your totals stay consistent.
- Spot-check your rounded punches against the raw times now and then; if rounding always lands in the employer's favor, flag it.