Date Calculator answers two common questions: how many days are there between two dates, and what date is it X days (or weeks, months or years) from a given date? It's useful for project deadlines, notice periods, visa stays, pregnancy and due-date planning, contract terms, countdowns and anniversaries.
The day count is shown as total days, as weeks plus days, as years, months and days, and as business days (Monday to Friday). Adding months handles different month lengths correctly. For example, 31 January plus one month gives the last day of February.
How to use the Date Calculator tool
- To count days, pick a start and end date, and tick 'Include end date' to count both ends.
- To add or subtract, pick a start date, choose Add or Subtract, then enter an amount and unit.
- Results update automatically.
Features
- Days, weeks, months and years between dates.
- Business day count (Mon–Fri).
- Add or subtract days, weeks, months or years.
- Correct month-end and leap-year handling.
- Instant and private.
Tips for best results
Use 'Include end date' when counting things like hotel nights versus days of an event: 1–3 March is 2 nights but 3 days inclusive. The business day count excludes weekends but not public holidays, so subtract those for your country. For your exact age, use the Age Calculator.
Counting days on a calendar by hand is easy to get wrong, especially across months of different lengths, leap years or year boundaries. This calculator uses exact calendar arithmetic in UTC, so the results aren't affected by daylight saving time changes in your time zone.
Compatibility and limits
The Date Calculator gives results instantly as you type and works on phones, tablets and computers. Results are rounded for display but calculated at full precision. The numbers you enter are not saved, so refreshing the page starts a new calculation. Results are estimates for general information, so for important medical, legal or financial decisions, please check with a qualified professional.
Privacy: your files never leave your device
All calculations happen in your browser. The numbers you enter, such as dates of birth, weights or loan amounts, are never sent to a server or stored.
Frequently asked questions
How do I count days between two dates?
Enter both dates in the first calculator. The number of days appears instantly.
Does it include the end date?
Only if you tick 'Include end date'.
Are holidays excluded from business days?
No. Only Saturdays and Sundays are excluded.
What happens when adding a month to 31 January?
You get the last day of February (28th or 29th).
Is any data stored?
No. Everything is calculated in your browser.