Time Calculator Cardamon

Add, subtract, multiply, and divide hours and minutes, then convert to any unit. Keep a running history and work out per-unit rates. Free, offline, no sign-up.

Time Calculator adds, subtracts, multiplies, and divides durations, then converts the result into any unit you need. Type 5h 30m + 2h 15m and read the total. Work out 8h 15m × 3, or split 3d 4h ÷ 2. It carries minutes into hours for you, so you never do it by hand.

WHAT YOU CAN DO • Add and subtract times: 40h − 6h 30m gives you the difference in one tap. • Multiply and divide a duration by a number: 45m × 12, or 90m ÷ 4. • Convert any result across units, from years down to milliseconds. • Read the answer your way: hours and minutes, decimal hours, or a clock format like H:MM:SS. • Save past calculations to a history and reuse them. • Pick light, dark, or system theme. Theme stays free.

COMMON USES • Timesheets and payroll: total the week, subtract breaks, find overtime. • Billing: turn tracked time into round numbers or decimal hours. • Cooking, workouts, and video editing: add up steps and segments. • Planning: split a duration across people or sessions.

PRO (one-time unlock) Unlock the extras once and keep them: • The Rate calculator: cost or output per hour, minute, or any unit. • Every result format beyond the core set. • All keypad presets plus a custom unit picker. • Unlimited history. The core calculator, unit conversion, and every theme stay free. No ads.

PRIVACY The math runs on your device, and your history stays on your phone. Analytics consent controls live in Settings, and you can open the full policy any time.

Questions or ideas? Email support@cardamon.org. We read every message.