Calculators
Date Calculator
Compute date differences in days or add/subtract a day offset to plan deadlines and timelines. Simple, accurate calendar math in your browser.
Runs entirely in your browser. Your data never leaves this device.
- Date difference
- Add/subtract days
- Weekday labels
- ISO dates
- Copy results
Workspace
Client-side · No upload
How it works
- Choose difference or add/subtract mode.
- Pick dates or a start date + day offset.
- Copy the result.
Key features
- Date difference
- Add/subtract days
- Weekday labels
- ISO dates
- Copy results
FAQ
Inclusive days?
Difference counts whole midnights between dates (end − start).
Business days?
MVP uses calendar days, not business-day calendars.
Private?
Yes.
Related?
Timestamp Converter handles Unix epoch times.
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