Time Calculator

Find elapsed time between two clock times, or add or subtract a duration from a clock time. Handles overnight and next-day offsets.

min
Elapsed time (hours)
8.5
Hours:minutes8h 30m
Decimal hours8.5
Minutes510
OvernightNo
Advertisement

How to use this time calculator

A time calculator answers two different Google queries: “how many hours between 8:45 and 5:15” and “what time is 8:45 plus 8 hours 30 minutes.” Pick the mode. Overnight elapsed time still works (22:00 to 06:00 is 8 hours).

Formula

Elapsed = end − start (+24h if overnight). Add/subtract: start minutes ± duration, wrapped on a 24-hour clock, with a day offset.

Worked example

Elapsed 08:45 to 17:15 is 8.5 hours. Add 8h 30m to 08:45 and the clock reads 17:15.

Related calculators

More work hours calculators

  • Time Card CalculatorEnter clock-in, clock-out, break, and a second shift for Monday through Sunday. Instant weekly hours, overtime after 40, decimal hours, and estimated gross pay.
  • Work Hours CalculatorEnter hours worked each day (not clock times). Get weekly total, regular vs overtime, hours:minutes, and optional pay.
  • Hours Worked CalculatorCalculate hours worked from one clock-in and clock-out, including unpaid break and overnight shifts. Shows decimal hours and hours:minutes.
  • Hours CalculatorAdd up to six hour-and-minute segments (jobs, tasks, or split shifts) into one total in decimal hours and hours:minutes.
  • Clock In / Clock Out CalculatorConvert clock-in and clock-out punches to paid hours with unpaid break and payroll rounding: none, 5, 10, 15 minutes, or the 7-minute rule.
  • Overtime CalculatorSplit a week of daily hours into regular, overtime, and double-time using FLSA weekly-40, daily-8, or both (California-style). Optional pay.

Frequently asked questions

What time is 8 hours after 9:00?

Choose Add duration, start 09:00, duration 8h 0m → 17:00.

Does elapsed time include overnight?

Yes. If the end clock is earlier, it is treated as the next day.

Difference vs Hours Worked?

Hours Worked subtracts an unpaid break. Elapsed mode here is raw clock difference.

Results are estimates for informational purposes and are not financial, legal, or professional advice. Last reviewed 2026-08-19.