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A date difference calculator computes the exact number of days, weeks, months, and years between two calendar dates. Useful for countdown timers, age calculations, contract duration, and deadline tracking. Accounting for leap years makes this non-trivial: 2000 had 366 days, most centuries do not.

Guide étape par étape

1. 1Enter start and end dates
2. 2Calculate difference in days
3. 3Convert to years/months/days

Exemples résolus

Erreurs courantes à éviter

• ✕Not double-checking results
• ✕Ignoring edge cases

Questions fréquentes