CCalcPro

Time Calculator

Add, subtract, and calculate time durations. Find the difference between two times or calculate what time it will be.

::
hours
:
min
:
sec

How to Calculate Time

Time calculations follow a base-60 system: 60 seconds in a minute and 60 minutes in an hour. When adding or subtracting time, carry over values when they exceed their limits — for example, 75 minutes becomes 1 hour and 15 minutes.

Adding time: Add hours, minutes, and seconds separately, then carry: 2:45 PM + 1h 30m → 3:75 PM → 4:15 PM.

Subtracting time: Borrow when needed: 3:15 PM − 45m → borrow 1h → 2:75 PM − 45m → 2:30 PM.

Time Calculation Examples

CalculationResultUse Case
9:00 AM + 8h5:00 PMWork shift
2:30 PM + 3h 45m6:15 PMMeeting end
5:00 PM − 2h 30m2:30 PMStart time
11:45 PM + 2h1:45 AM (+1 day)Overnight
9 AM to 5:30 PM8h 30mHours worked

Common Use Cases

Work hours tracking: Calculate total hours worked per day, week, or pay period using the "Time Between" mode.

Scheduling & planning: Find meeting end times, delivery estimates, or travel arrival times by adding durations.

Cooking & baking: Add preparation and cooking times to know when food will be ready.

Exercise & sports: Track workout durations, rest periods between sets, or race split times.

Time Zones

This calculator uses your local time. To convert between time zones, add or subtract the UTC offset difference. For example, to convert EST (UTC−5) to PST (UTC−8), subtract 3 hours.

Common offsets: EST (UTC−5), CST (UTC−6), MST (UTC−7), PST (UTC−8), GMT/UTC (±0), CET (UTC+1), IST (UTC+5:30), JST (UTC+9).

Related Calculators

Related Calculators

Frequently Asked Questions