Date Calculator

Compute exact duration between two dates, add or subtract days, find the day of the week for any date, or count down to a target date.

How to use this calculator

1. Select mode.
2. Enter dates.
3. Read result.

Formula & method

Gregorian Date Arithmetic

Days = Date2 - Date1

Exact UTC date offsets.

Example

Jan 1, 2025 to Jan 1, 2026 = 365 days.

Key insights

• Leap years add a 366th day.
• Standard year has 52 weeks and 1 day.

How to interpret your result

Total Days

Exact count of days between dates.

Frequently asked questions

Does this handle leap years?

Yes, February 29 is automatically included.

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