Date Difference Calculator
Count the days, weeks, and months between two dates.
That's 0 years, 11 months, and 30 days.
Use on any page (bookmarklet)
Want Date Difference Calculator without leaving the page you're on? Drag the button below to your bookmarks bar, then click it on any website to open Date Difference Calculator right there — it runs entirely in your browser.
Use responsibly: a bookmarklet runs on whatever page you click it on. Avoid sensitive sites such as online banking, payment, or healthcare pages — you run it at your own risk. Everything is processed locally and no data is sent anywhere. See our Terms.
- Show your bookmarks bar if it's hidden — Ctrl+Shift+B (⌘+Shift+B on Mac).
- Drag the button above onto the bookmarks bar.
- Open any website and click the bookmark — the Date Difference Calculator panel appears in the top-right corner. Use ✛ to move it between corners, or ›/‹ to tuck it against the edge and pull it back out.
- Click the bookmark again (or the ✕) to close it.
Note: a few sites with strict security policies may block bookmarklets.
Examples
Across a full year
Input
2025-01-01 → 2025-12-31
Output
364 days · 52 weeks · 0y 11m 30d
A short span
Input
2025-03-01 → 2025-03-15
Output
14 days · 2 weeks
About this tool
This free online date difference calculator counts the time between two dates. Pick a start and end date and instantly see the total days, the number of weeks, and a clean years / months / days breakdown. Everything runs in your browser with no upload.
How to use
- Choose a start date.
- Choose an end date.
- Read the total days, weeks, and the calendar breakdown.
Common uses
Counting days until a deadline or event, working out a project duration, tracking time since a milestone, and calculating notice periods or contract lengths.
Frequently asked questions
How do I count the days between two dates?
Pick a start and end date and the calculator shows the total number of days between them, plus weeks and a years/months/days breakdown.
Is this date difference calculator free?
Yes — it's a completely free online date difference calculator with no sign-up.
Does it include both the start and end dates?
It counts the number of days from the start date to the end date (the span between them). To count inclusive days, add one to the total.
Does the order of the dates matter?
No. If the end date is earlier than the start date, the calculator uses the absolute difference, so you always get a positive result.
How are months and years counted?
The breakdown counts complete calendar years and months first, then the leftover days — the same way you'd say 'one year, two months, and three days'.
Is my data uploaded anywhere?
No. The calculation runs entirely in your browser with no upload.
Learn more
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