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Date Format Converter

Date & Time

Date Input

Paste a written date, a slash-separated date, a Unix timestamp, or an ISO 8601 string.

Output Formats

Custom Format Pattern (Optional)

Tokens: YYYY, YY, MMMM, MMM, MM, M, DD, D, dddd, ddd, HH, H, hh, h, mm, m, ss, s, A, a — wrap literal text in [ ] (e.g. [at]).

About This Tool

Date Format Converter – Reformat Any Date Into Any Style

Every system seems to want a date written a different way. A spreadsheet expects MM/DD/YYYY, an API expects 2026-07-16T00:00:00Z, an email header expects Thu, 16 Jul 2026 00:00:00 GMT, and a colleague overseas expects 16/07/2026. The Date Format Converter takes a single date and renders it in every one of these forms at once, so you never have to manually rewrite a date again or guess whether 03/04/2026 means March 4th or April 3rd.

Formats Supported

Paste or pick a date and the tool simultaneously produces the US format (MM/DD/YYYY), the European format (DD/MM/YYYY), a YYYY/MM/DD sortable form, full ISO 8601, RFC 2822 / HTTP-date (the style used in email and HTTP headers), a locale-aware long-form written date like "Thursday, July 16, 2026", and the equivalent Unix timestamp in both seconds and milliseconds. Toggle any of these on or off in the Output Formats panel to keep the results table focused on what you actually need.

Auto-Detection and Explicit Input Formats

By default the converter auto-detects whether your input is a Unix timestamp, an ISO 8601 string, a common slash- or dash-separated date, or free text like "July 16, 2026". For genuinely ambiguous input such as 03/04/2026, switch the Input Format selector to US or EU explicitly so the day and month are never misread.

Custom Format Patterns

When none of the built-in formats match what you need, define your own using standard tokens: YYYY and YY for the year, MM/M and MMMM/MMM for numeric or written months, DD/D for the day, dddd/ddd for the written weekday, HH/hh for 24- or 12-hour time, and mm/ss for minutes and seconds. Wrap any literal text you want preserved, like the word at, in square brackets — for example dddd, MMM D YYYY [at] HH:mm renders as Thursday, Jul 16 2026 at 14:30. The preview updates as you type, and an inline error appears if the pattern contains an unrecognized token.

Time Zones and Locales

If your input already carries a UTC offset or a Z (an ISO string or a Unix timestamp), that offset defines the exact instant in time, and the Time Zone selector only changes how the result is displayed. Otherwise, the selected time zone tells the tool how to interpret the wall-clock date and time you entered. The Locale selector controls the language used for written month and weekday names in the long-form output and in custom patterns that use MMMM or dddd, so the same date can read as "July 16" or "16 juillet" depending on your audience.

Converting Many Dates at Once

Switch to Batch mode and paste a newline- or comma-separated list of dates to convert all of them in one pass — handy for cleaning up a pasted spreadsheet column or a CSV export. Each entry is converted independently, so a single malformed row is flagged without blocking the rest, and the full results table can be exported as a CSV file.

Why formats matter
Numeric date formats like MM/DD/YYYY and DD/MM/YYYY are only unambiguous within a single locale. When sharing dates across systems, teams, or countries, standards like ISO 8601 and RFC 2822 remove the guesswork because their component order and separators never change.

Frequently Asked Questions

Is the Date Format Converter free?

Yes, Date Format Converter is totally free :)

Can I use the Date Format Converter offline?

Yes, you can install the webapp as PWA.

Is it safe to use Date Format Converter?

Yes, any data related to Date Format Converter only stored in your browser (if storage required). You can simply clear browser cache to clear all the stored data. We do not store any data on server.

How does the Date Format Converter work?

Type or paste a date, choose its input format (or leave it on auto-detect), and the tool instantly renders it side by side as US, EU, ISO 8601, RFC 2822/HTTP-date, a long written form, and Unix timestamp — plus any custom pattern you define using tokens like YYYY, MM, and dddd.

What formats can I convert between?

US (MM/DD/YYYY), EU (DD/MM/YYYY), YYYY/MM/DD, ISO 8601, RFC 2822/HTTP-date, a locale-aware long-form written date, Unix timestamps in seconds or milliseconds, and any custom token pattern you build yourself.

How do custom format patterns work?

Build a pattern using tokens such as YYYY (year), MM (month), DD (day), HH:mm:ss (24-hour time), or dddd/MMMM for full weekday and month names, and see a live preview as you type. Wrap literal text in square brackets, like [at], to keep it from being interpreted as a token.

Does it handle time zones and locales?

Yes. Pick an IANA time zone to control how the date/time is displayed, and a locale (like en-US or fr-FR) to control the language used for written month and weekday names in the long-form and custom pattern outputs.

Can I convert many dates at once?

Yes. Switch to batch mode and paste a newline- or comma-separated list of dates; each entry is converted independently, invalid entries are flagged without blocking the rest, and you can export all results as a CSV file.

How accurate is the auto-detection of input formats?

Auto-detection recognizes Unix timestamps, ISO 8601 strings, common slash/dash-separated dates, and free-text dates, auto-correcting obviously swapped day/month values. For genuinely ambiguous dates like 03/04/2026, choose the input format explicitly to avoid misinterpretation.