Time Duration Arithmetic

Add and subtract clock durations

Payroll adjustments, broadcast logs, and workout timers often list several HH:MM:SS segments. Enter one duration per line, prefix with - to subtract, and watch a running total plus the final signed net duration. Hours are not capped at 23, multi-day totals stay in hour:minute:second form.

Typical workflows

1. Sum billed hours from a text export before invoicing.
2. Combine FFmpeg chapter lengths or podcast segment durations.
3. Net overtime minus break deductions on a single shift sheet.

For wall-clock elapsed time between two times of day, use Elapsed Time Calculator. For calendar date differences, try Find Date Difference.