Date and time calculators
Calendar maths is full of traps: months of different lengths, leap years and 29 February birthdays. These calculators handle them for you and show the result in years, months, weeks and days.
Frequently asked questions
How are leap years handled?
Every calculation uses the real calendar, including 29 February in leap years. Years divisible by 100 are leap years only when also divisible by 400, so 2000 was a leap year and 1900 was not.