Time Clock Calculator

A time clock records moments, not durations. A normal day with an unpaid lunch produces four punches: in, out for lunch, back from lunch, out for the day. The hours worked are the two gaps between the pairs, added together. The calculator above is loaded with such a day so you can see every step:

The 32 minutes between 12:02 and 12:34 are not worked and are not paid, so there is nothing to deduct separately: lunch is simply the gap between the two segments. If your clock only records in and out and lunch is taken off by the system, enter one segment and the lunch minutes in the break field instead; the arithmetic is the same.

Each segment is clock-out minus clock-in. 12:02 PM minus 7:56 AM is easiest in 24-hour time: 12:02 − 07:56 = 4 hours 6 minutes. The two segments add to 8 hours 6 minutes; 6 minutes is 6 ÷ 60 = 0.10 of an hour, so payroll sees 8.10 hours. A shift that crosses midnight, say 10:50 PM to 7:05 AM, is handled the same way; the calculator notices that the end is earlier than the start and counts into the next day.

Many time clocks do not store 7:56; they store 8:00. Rounding each punch to the nearest quarter hour is the oldest convention, and 29 CFR 785.48(b) allows it, along with rounding to the nearest tenth of an hour (6 minutes) or nearest 5 minutes, as long as the practice does not, over time, fail to pay employees for all the time they actually work. Choose the rounding step in the options and the calculator rounds every punch before it subtracts, exactly as a clock would. The same four punches give four different days:

Quarter-hour rounding cost this employee 6 minutes. On another day it gives minutes back: clocking in at 8:07 counts as 8:00. The regulation tolerates that only because the gains and losses are expected to cancel; a system that always rounds in the employer's favor, or a schedule where employees are told to punch in just before the rounding point and out just after it, is not neutral and does not comply. The 7-minute rule guide has the full quarter-hour table and the California cases that have narrowed rounding there.

If your pay stub shows rounded hours, enter your raw punches here with rounding off and then with the rule your employer uses. The difference over a pay period is the cost of rounding to you, and a persistent one-way difference is worth a conversation with payroll.

Pay is computed in decimal hours, so the last step of every time clock calculation is converting minutes to hundredths of an hour. Divide the minutes by 60: 6 minutes are 0.10, 20 minutes are 0.33, 45 minutes are 0.75. The common values are worth knowing by heart because they explain why 8:06 appears as 8.10 and 7:45 as 7.75 on the stub.

Clocks that round to the tenth of an hour do the conversion for you: every tenth is 6 minutes, so 8:06 is 8.1, 8:12 is 8.2 and 8:30 is 8.5. The minute-by-minute chart and the reverse conversion are on the hours to decimal page.

Daily results are easiest to check in hours and minutes, but a week should be added in minutes or in decimal, never by stacking the two columns of hh:mm as if they were decimals. Five days of 8:06, 7:52, 8:14, 8:03 and 7:48 are 486 + 472 + 494 + 483 + 468 = 2,403 minutes, which is 40 hours 3 minutes, or 40.05 hours. The week tab of the calculator does this and splits the total into regular and overtime hours according to the rule you select; the hours and minutes calculator adds or subtracts plain times without the pay logic.

Three minutes over 40 is overtime. Under 29 U.S.C. 207 every minute over 40 in the workweek is paid at one and a half times the regular rate; there is no grace margin in the statute. With a rate of 18.00 dollars the week above pays 40 × 18.00 + 0.05 × 27.00 = 721.35 dollars. Switch the overtime rule to California for daily overtime over 8 hours, which turns the 8:06 and 8:14 days into 20 minutes of daily overtime even in a short week.

A punched lunch is the accurate one. Out at 12:02, back at 12:34 is 32 minutes, not the 30 minutes on the schedule, and the calculator uses the 32. An automatic deduction takes a fixed 30 or 60 minutes from every day whether or not the lunch was taken in full. The deduction itself is lawful: under 29 CFR 785.19 a bona fide meal period of ordinarily 30 minutes or more is not hours worked, provided the employee is completely relieved of duty. It becomes a problem when the meal is cut short or skipped and nobody reverses the deduction, because the minutes worked through lunch are hours worked and must be paid.

If your employer auto-deducts, keep your own record of interrupted or missed lunches and have them corrected in the same pay period. Short rest breaks of about 5 to 20 minutes are paid time under 29 CFR 785.18 and should never appear as deductions; enter them as nothing at all, or use a second pair of punches only for the unpaid meal.

A forgotten clock-out does not erase the hours. The FLSA counts all work the employer knows about or has reason to know about, whether or not it was recorded (29 CFR 785.11 to 785.13), and the duty to keep accurate records of hours worked each day rests on the employer under 29 CFR 516.2. An employer may discipline an employee for repeatedly missing punches, but a rule that unpunched time is unpaid is not enforceable for non-exempt work.

The practical rule is: report the missed punch at once, state the actual time, and keep a copy of the correction. The time clock calculator is the quickest way to produce the figure, because you can enter the true times and read the hours and minutes the record should show. If the corrected punch is later edited again without your knowledge, the exported CSV from this page, dated and with your original entry, is your evidence.

Punches of a few seconds either side of the minute are a separate matter. Most clocks record seconds but display and pay in minutes; the calculator works in minutes for the same reason. The de minimis rule in 29 CFR 785.47 lets an employer disregard insubstantial periods of a few seconds or minutes only where recording them is impractical, and California does not recognise the rule at all, so a clock that systematically drops a minute at every punch is not covered by it.

All three share one engine, so a day entered here can be carried into the week with the button under the result, and the overtime, rounding and pay settings mean the same thing on every page. Nothing you type is sent anywhere; the entries stay in your browser.