Date Format Converter

01/02/2026 means 1 February in most of the world and 2 January in the United States. This tool shows any date in many formats side by side (ISO 8601, US, UK, dotted, compact, long, RFC 2822, ISO week and day-of-year) plus the full date in several languages, so you can choose one that nobody will misread.

How to use it

Choose a date.
Read the list of formats.
Copy the one you need.
Change the date to see the others update.

When it helps

Preparing dates for a database or API.
Matching the format a form expects.
Writing dates for readers in other countries.
Avoiding day and month mix-ups.

Good to know

ISO 8601 (year-month-day) is the least ambiguous format, and it sorts correctly as text.
Spelling out the month name removes all doubt in documents.
Times aren't included; this is about dates only.

Why formats differ

Different regions evolved different conventions: day-month-year in most of the world, month-day-year in the United States, and year-month-day in East Asia and in the international standard ISO 8601. Each is perfectly logical to the people who use it, which is why exchanges between regions cause confusion.

The tool shows each side by side, so you can pick one that your reader will understand without a second look.

Worked example: 3 April 2026

ISO gives 2026-04-03, the US format 04/03/2026, and the UK format 03/04/2026. The compact form is 20260403 and the day of the year is 93. Written out, it's Friday, 3 April 2026, and in ISO week form it's 2026-W14-5.

For international documents, choose the written month, such as 3 April 2026, which can't be misread.

Choosing a format for systems

Use ISO 8601 for data, file names and APIs. It sorts correctly as text, and every programming language reads it. For file names, use the compact or hyphenated version at the start, so folders list in order.

For people, follow local convention, but add the month name in anything that will be read across borders.

Formats in programming

Programming languages offer date formatting functions with codes like %Y-%m-%d in Python and yyyy-MM-dd in Java. The ISO format is the safest for data exchange, and many tools expect it. Time zones add further complexity: add a Z suffix for UTC or an offset such as +01:00.

RFC 2822 dates, such as Fri, 03 Apr 2026, appear in email headers and some web feeds.

Avoiding date mix-ups

When a date could be read two ways, such as 04/05/2026, spell out the month. A single ambiguous date in a contract or invoice can cause a costly misunderstanding.

Sorting by date

Dates written year first sort correctly as plain text, which is why the ISO form is the best choice for file names, spreadsheets and databases. Month-first and day-first formats sort in the wrong order.