How it works
How to use the Date Calculator
Enter two dates
Pick a start and end date — or switch to “Add or subtract time” to add years, months, weeks, days or business days to a date.
Read the results
Every equivalent value is listed, with the most relevant one highlighted.
Copy what you need
Each result has its own copy button.
About the Date Calculator
Find the exact difference between two dates in years, months and days, plus total days, business days, weeks, hours and minutes. Or add and subtract time — including business days that skip weekends.
Built for developers
Why developers use it
Private by design
Runs 100% in your browser. Nothing you paste is uploaded, logged or stored on a server.
Instant results
Output updates as you type, with precise error locations when something is wrong.
Works offline
Once loaded, the tool keeps working without a connection. Install it as an app if you like.
Free, no sign-up
No accounts, no limits, no watermarks.
FAQ
Frequently asked questions
Is my data uploaded anywhere?
No. Everything runs locally in your browser — nothing you type, paste or open is sent to a server, logged or stored. The tool keeps working offline once the page has loaded.
Keep going
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