Many employers don't pay employees for their exact, to-the-second clock-in and clock-out times, they round each punch to the nearest interval first, commonly 5, 6, or 15 minutes, and calculate paid hours from the rounded times instead. This isn't arbitrary, it's a long-standing payroll practice meant to simplify timekeeping, and it follows a specific, symmetric rule rather than always rounding in the employer's or employee's favor.
The midpoint rounding rule
The standard approach, often called the "7-minute rule" when applied to 15-minute intervals, rounds each clock punch to the nearest 15-minute mark using the punch's position relative to the midpoint of that interval. A clock-in anywhere from :00 to :07 rounds down to the interval's start; a clock-in from :08 to :14 rounds up to the next interval. So 9:07 rounds down to 9:00, while 9:08 rounds up to 9:15, a single minute's difference in the raw punch time that determines which direction the rounding goes. The same rule applies to clock-out times, and to whatever rounding interval a given employer uses, 5-minute and 6-minute (rounding to the nearest tenth of an hour) rounding follow the identical midpoint logic, just with a shorter interval.
Why rounding is supposed to average out to neutral
The reason midpoint rounding is generally considered fair (and is the basis for rounding rules recognized in various wage-and-hour regulations) is that, applied consistently over many punches, it should round in the employee's favor roughly as often as it rounds in the employer's favor, since a punch is equally likely to fall in the first or second half of any given interval over a large enough sample. A rounding policy that instead always rounds clock-ins up and clock-outs down (systematically shrinking paid time in every case) doesn't have this neutral property and is where rounding practices tend to run into legal problems, since it consistently benefits one side rather than averaging out.
From rounded punches to total pay
Once both the clock-in and clock-out times are rounded, calculating total hours worked from them is the same subtraction covered in our guide on calculating hours worked from clock-in and clock-out times, including the same overnight-shift handling if a rounded shift happens to cross midnight. The Time Card Calculator applies the rounding step first and then runs that duration calculation, so the final paid-hours figure already reflects the employer's rounding policy rather than the raw punch times.