Date Calculator: Days Between Dates & Add Days
Find the interval between two dates or add and subtract calendar time from a starting date.
Your files and tool inputs never leave this browser. This tool is free to use, with no account and no limit.
How to use this tool
- Choose the date difference or add/subtract mode.
- Enter two dates, or a starting date and an amount of time.
- Review the resulting date or interval, which updates as you type.
Calendar dates for everyday planning
Use total days to compare deadlines or the add/subtract mode to plan a date ahead. This is a calendar calculator, not a business-day calculator: weekends and public holidays are not excluded. Month and year operations follow JavaScript calendar rollover rules, so check month-end and leap-day results.
Frequently asked questions
- How are months and years counted?
- The tool uses calendar dates rather than fixed 30-day months. Adding months or years follows JavaScript date rollover, so an invalid day in the destination month can roll into the following month. Check month-end results.
- Does the calculator exclude weekends?
- No. It counts calendar time, including weekends. It does not have a country-specific public holiday calendar.