Date Format Converter
A Date Format Converter lets you parse any date or date-time string and instantly display it in multiple international formats. Whether you need ISO 8601 for APIs, MM/DD/YYYY for US documents, DD/MM/YYYY for European forms, or a Unix timestamp for programming, this tool handles them all from a single input.
Different regions and software systems store and display dates in incompatible ways. Misreading a date format is a common source of bugs and miscommunication. This converter removes the ambiguity by showing your date in every major format at once, with one-click copying so you can paste the right format wherever it's needed.
How it works
Parsing uses the ECMAScript Date object (ISO 8601 is parsed natively). The Unix timestamp is calculated as Math.floor(date.getTime() / 1000), where getTime() returns milliseconds since 1970-01-01T00:00:00Z. US and EU formats are composed by zero-padding month, day, and year components. Long localized output uses the browser's Intl.DateTimeFormat API with the appropriate locale.
Use cases
- Converting a date from an API response (ISO 8601) into a human-readable format for display
- Translating US dates (MM/DD/YYYY) into EU format (DD/MM/YYYY) when working with international teams
- Obtaining the Unix timestamp of a specific date for use in database queries or shell scripts
- Quickly finding the weekday for any date without a calendar
- Cross-checking date inputs before inserting them into spreadsheets, contracts, or legal documents
Frequently asked questions
What is the ISO 8601 date format?
ISO 8601 is the international standard that writes dates from largest to smallest unit: YYYY-MM-DD, such as 2026-07-13, with an optional time part like 2026-07-13T14:30:00Z. Because the components always appear in the same order, it is unambiguous and sorts correctly as plain text, which is why APIs and databases prefer it.
How do I convert a date to a Unix timestamp?
A Unix timestamp is the number of seconds elapsed since 1970-01-01T00:00:00 UTC (the Unix epoch). In JavaScript it is computed as Math.floor(date.getTime() / 1000), since getTime() returns milliseconds. For example, 2000-01-01T00:00:00Z corresponds to the timestamp 946684800.
What is the difference between MM/DD/YYYY and DD/MM/YYYY?
MM/DD/YYYY puts the month first and is standard in the United States, while DD/MM/YYYY puts the day first and is used in most of Europe and Latin America. A date like 03/04/2026 therefore means March 4 in the US but April 3 in Europe. This ambiguity is exactly why unambiguous formats such as ISO 8601 are recommended for data exchange.
Are Unix timestamps in seconds or milliseconds?
The classic Unix timestamp is in seconds, but many programming environments — including JavaScript's Date.getTime() — work in milliseconds. A 13-digit value is almost certainly milliseconds and a 10-digit value is seconds for contemporary dates. To convert, divide milliseconds by 1000 (or multiply seconds by 1000).
How can I find the day of the week for any date?
Enter the date into this converter and the weekday is shown alongside the other formats. Internally, the tool parses the date with the ECMAScript Date object and formats the weekday using the browser's Intl.DateTimeFormat API, so no manual algorithm or calendar lookup is needed.