Date Calculator
Calculate the difference between two dates or add/subtract time units from a date. Free, private, and 100% client-side.
Local only
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How to use
- Choose a mode: diff, add, or subtract.
- For diff, enter two dates separated by a newline.
- For add/subtract, set the unit and amount, then enter one date.
- Read the result.
Frequently asked questions
- How do I calculate the difference between two dates?
- Select diff mode, then enter two dates separated by a newline. The result is the difference in the selected unit.
- How do I add or subtract time from a date?
- Select add or subtract mode, set the unit and amount, then enter a single date. The result is the computed date in ISO 8601.
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