How do I use the time clock rounding calculator?
- Enter the actual punches as they appear on the clock, such as 7:53 AM and 4:22 PM, plus any unpaid break.
- Choose the rounding increment: 15 minutes (7-minute rule), 10, 6 (tenths) or 5 minutes.
- Compare actual and rounded hours. The difference shows how many minutes rounding added or removed. Add a rate to see the dollar effect.
When does a punch round up or down?
With nearest rounding, a punch exactly halfway rounds up. That gives these cut-offs: 15 minutes, 7 down / 8 up; 10 minutes, 4 down / 5 up; 6 minutes, 2 down / 3 up; 5 minutes, 2 down / 3 up. A punch at 11:53 PM with 15-minute rounding rounds to midnight. The chart below shows every minute of an hour for 15-minute and tenth-of-an-hour rounding.
| Punch at | 15-min rounds to | Tenths |
|---|---|---|
| :00 | :00 | .0 |
| :01 | :00 | .0 |
| :02 | :00 | .0 |
| :03 | :00 | .1 |
| :04 | :00 | .1 |
| :05 | :00 | .1 |
| :06 | :00 | .1 |
| :07 | :00 | .1 |
| :08 | :15 | .1 |
| :09 | :15 | .2 |
| :10 | :15 | .2 |
| :11 | :15 | .2 |
| :12 | :15 | .2 |
| :13 | :15 | .2 |
| :14 | :15 | .2 |
| :15 | :15 | .3 |
| :16 | :15 | .3 |
| :17 | :15 | .3 |
| :18 | :15 | .3 |
| :19 | :15 | .3 |
| Punch at | 15-min rounds to | Tenths |
|---|---|---|
| :20 | :15 | .3 |
| :21 | :15 | .4 |
| :22 | :15 | .4 |
| :23 | :30 | .4 |
| :24 | :30 | .4 |
| :25 | :30 | .4 |
| :26 | :30 | .4 |
| :27 | :30 | .5 |
| :28 | :30 | .5 |
| :29 | :30 | .5 |
| :30 | :30 | .5 |
| :31 | :30 | .5 |
| :32 | :30 | .5 |
| :33 | :30 | .6 |
| :34 | :30 | .6 |
| :35 | :30 | .6 |
| :36 | :30 | .6 |
| :37 | :30 | .6 |
| :38 | :45 | .6 |
| :39 | :45 | .7 |
| Punch at | 15-min rounds to | Tenths |
|---|---|---|
| :40 | :45 | .7 |
| :41 | :45 | .7 |
| :42 | :45 | .7 |
| :43 | :45 | .7 |
| :44 | :45 | .7 |
| :45 | :45 | .8 |
| :46 | :45 | .8 |
| :47 | :45 | .8 |
| :48 | :45 | .8 |
| :49 | :45 | .8 |
| :50 | :45 | .8 |
| :51 | :45 | .9 |
| :52 | :45 | .9 |
| :53 | next hour | .9 |
| :54 | next hour | .9 |
| :55 | next hour | .9 |
| :56 | next hour | .9 |
| :57 | next hour | next hour |
| :58 | next hour | next hour |
| :59 | next hour | next hour |
Worked examples
Example 1: early in, early out
Punches 7:53 AM and 4:22 PM, 15-minute rounding. 7:53 is 7 minutes before 8:00, so it rounds to 8:00 AM; 4:22 is 7 minutes past 4:15, so it rounds to 4:15 PM. Actual time 8:29, paid time 8:15, 14 minutes less.
Example 2: late in, late out
8:07 AM to 5:08 PM with a 30-minute lunch. 8:07 rounds down to 8:00 and 5:08 rounds up to 5:15, so the actual 8:31 becomes 8:45 (+14 minutes). With 6-minute rounding the same day is 8:30.
Example 3: is it neutral over a week?
Five shifts (7:58 AM–4:31 PM, 8:06 AM–4:29 PM, 8:02 AM–4:37 PM, 7:54 AM–4:24 PM, 8:09 AM–4:33 PM), each with a 30-minute lunch. Actual time is 39:55. Nearest-15 rounding gives 39:45 (−10 min). Always rounding down would give 40:00 (−-5 min), which is the kind of one-way rounding the Department of Labor does not allow.
What does the law say about rounding?
The federal rule is short. Employers may round start and stop times to the nearest 5 minutes, tenth or quarter of an hour, as long as rounding "will not result, over a period of time, in failure to compensate the employees properly for all the time they have actually worked" (29 CFR 785.48(b)). In practice that means rounding both ways, and checking now and then that totals are not drifting against workers. Many employers now pay to the exact minute instead, which modern time clocks make easy.
To total a full week of exact punches, use the time card calculator. To convert the minutes to decimal for payroll, see the minutes to decimal chart.