Date Calculator

Calculating the gap between dates

Find the number of days, weeks, months and years between two dates, or add and subtract a period from a date. It is useful for deadlines, pregnancy and project planning, notice periods, loan terms and age eligibility checks.

How it works

The tool converts each date into a day count and subtracts. Months and years are counted as complete calendar units, so leap years and months of different length are handled correctly.

Worked example

From 1 January 2026 to 1 July 2026 there are 181 days, which is 25 weeks and 6 days, or 6 months exactly.

Points to check

• Decide whether the end date should be counted. Many forms count both ends, which adds one day.
• Business-day calculations exclude weekends and holidays, which this simple tool does not.