Date Formatter

How to use Date Formatter

1. Open Date Formatter — it runs entirely in your browser with no setup.
2. Paste or type your input into the text area, or upload a file where supported.
3. Set any options you need. The result appears in the output panel — there is no upload step and no waiting on a server.
4. Review the output instantly; large inputs are handled locally without lag.
5. Copy the result to your clipboard or download it. Your data never leaves the page.

Why use Date Formatter?

• 100% free with no limits, no sign-up and no watermarks.
• Private by design — your data are processed in your browser and never uploaded to a server.
• Fast and lightweight, with instant results even on a phone or a slow connection.
• Works everywhere — any modern browser on Windows, macOS, Linux, Android or iOS.
• Part of a full developer tools suite, so related date formatter tasks are one click away.

What people use Date Formatter for

• Producing a date string in the exact format a report or an import file expects.
• Converting between display formats without writing formatting code.
• Checking what a format token pattern will actually output.

Date Formatter: limits and things worth knowing

• Format tokens are not standardised across libraries. YYYY means the calendar year in Moment and Day.js while yyyy is the equivalent in date-fns and Java; getting this wrong is common when porting code.
• Uppercase DD is day-of-month and lowercase dd can mean day-of-week depending on the library. Check the reference rather than assuming.
• The ISO week-year token (often GGGG or YYYY in strict ISO libraries) differs from the calendar year in the days around New Year, which produces off-by-one-year bugs every January.
• A date without a timezone is ambiguous. The same instant is two different calendar dates on opposite sides of the world, which matters for anything dated near midnight.

Is it private and secure?

Your privacy is built in. Date Formatter runs completely on your device, so whatever you enter stays in your browser and is never transmitted, logged or stored on any server.

Network activity: none. Nothing is sent and nothing is fetched. This tool makes no network request at all once the page has loaded — which is why it keeps working if your connection drops.

You do not have to take that on trust — our privacy proof page publishes the Content-Security-Policy that enforces it, lists every third party it permits, and shows how to verify the whole claim yourself.

Learn more

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