Date Calculator
Difference between dates, add and subtract durations.
Difference
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Enter two valid dates (YYYY-MM-DD).
Examples
- Difference2026-01-01 → 2026-03-14→ 72 days (2 months 13 days)
- Add duration2026-05-01 + 90 days→ 2026-07-30
What it does
Date Calculator computes the difference between two dates (in days, weeks, months, and years), and lets you add or subtract a duration from a date while respecting calendar semantics — adding a month to January 31 lands on February 28 (or 29 in a leap year), not on March 3.
When you need it
Planning a project deadline, counting down to a trip, calculating an eligibility window, or working out a renewal date — Date Calculator gives you an exact answer without spreadsheet gymnastics.
How it works locally
All date math is performed by a pure TypeScript engine that runs in your browser. No date you enter is sent to a server or stored in a database. The same engine powers the Quick Command bar.