Three tools in one: convert between seconds, minutes, hours, days, weeks, months and years — add or subtract two durations — or find the exact duration between two times of day.
Convert mode converts any amount from one time unit to another — enter a number, choose the source unit and target unit, then click Calculate. Add / Subtract mode lets you add or subtract two durations expressed in hours, minutes and seconds. Difference mode finds the exact duration between two times of day, handling overnight spans automatically (e.g. 11 PM to 7 AM correctly returns 8 hours).
Results from this calculator are estimates based on standard Gregorian calendar and time-duration arithmetic and are provided for general informational purposes. Rounding, regional standards and manufacturer variations can cause small differences from official or brand-specific figures.
For decisions where precision is critical — engineering, construction or legal contexts — verify results with a qualified professional or an official reference source.
This calculator uses standard Gregorian calendar and time-duration arithmetic. The underlying logic was built and manually cross-checked against independent reference calculators and textbook worked examples across dozens of test cases before publication.
Every formula on elCalculador is reviewed by our editorial team for mathematical accuracy, and pages are re-audited whenever a calculator's logic or inputs are updated.