Days Between Two Dates
Pick a start and end date to see the total days — and, if you need it, business days only.
Days Until a Date
How long until August 13, September 17, Christmas, or any date you pick.
Days Since a Date
How long ago was September 30, or any past date you enter.
Days Ago / Days From Today
Enter a number like 90 or 2015 to jump straight to that date.
Add or Subtract Time From a Date
Choose a starting date, then add or subtract any mix of years, months, weeks, and days.
How to Use This Calculator
Five tools, one page. Pick the one that matches what you need, enter your date (or dates), and press Calculate.
- Pick a tool. Days Between for two known dates, Days Until / Days Since for a single date relative to today, Days Ago / From Today for a quick number-of-days lookup, or Add/Subtract for full control over years, months, weeks, and days.
- Enter your date or number. Every date field uses your browser's own date picker, so there's nothing to type in a specific format.
- Press Calculate. The result appears right below the tool, including business-day counts where relevant.
- Reset any time. Each tool has its own reset button so you can run a fresh calculation without reloading the page.
Leap years, short months, and month-end edge cases (like adding a month to January 31) are all handled automatically using the Gregorian calendar.
Frequently Asked Questions
Use the "Days Between Two Dates" tool at the top of the page. Enter a start date and an end date, and it instantly shows the total number of calendar days between them, with an option to also show business days only (excluding weekends).
Use the "Days Until a Date" tool. Pick the target date (for example August 13 or December 25) and it shows exactly how many days remain from today. If the date has already passed this year, it tells you that too instead of showing a negative number.
Use the "Days Since a Date" tool. Pick the past date and it shows exactly how many days have passed since then, up to today.
Use the "Days Ago / Days From Today" tool. Enter a number such as 90 or 2015, choose "ago" or "from today", and it returns the exact calendar date.
Yes. Use the "Add or Subtract Time From a Date" tool. Choose a starting date, choose forward or backward, and enter any combination of years, months, weeks, and days — the resulting date updates automatically.
Yes. All calculations follow the Gregorian calendar's leap year rules, so results stay accurate across February 29 and across multi-year spans.
Total days count every calendar day between two dates. Business days count only Monday through Friday and exclude weekends. Turn on the business days option in the "Days Between Two Dates" tool to see both figures at once — useful for shipping estimates, notice periods, and work schedules.
Yes. Every calculation runs locally in your browser using JavaScript. No dates or results are sent to any server.