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Time Addition Calculator

Add hours and minutes to any time — shift schedules, compute end times, total durations. Add 8h30m to 9:00 for shift end — free, local, no signup.

100% Local Browser Native

How to Use the Time Addition Calculator

1. Enter start time

Current time in either format.

2. Add the duration

Hours and minutes to shift.

3. Read the result

End time with next-day flag.

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Frequently Asked Questions

What time is 8h30m after 9:00?

17:30 (5:30 PM) — hours add directly, minutes carry past 60. Overnight spans roll into next-day notation automatically.

Add multiple durations?

Yes — chain entries: 2h15m + 1h45m + 30m totals 4h30m. Timesheets add weekly columns the same way.

12h or 24h output?

Both display where relevant — 17:30 reads 5:30 PM. Roster and payroll contexts prefer 24h.

Do time sums upload?

No — math runs locally in your browser. Nothing leaves your device.

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Last updated October 2026