France code postal validator
How the code postal format works
- Format
- 5 digits
- Example
- 75008
Things to watch for
- Format-only check — does not confirm the code postal actually exists
- Always exactly 5 digits; the first 2 digits usually match the département number
^[0-9]{5}$A French code postal is the 5-digit postcode La Poste uses to route mail, written after the city name — for example 75008 for the 8th arrondissement of Paris. Anyone validating a shipping address, a checkout form, or a spreadsheet of French customer records needs the code to be the right length and shape before it’s trusted downstream.
Because the code is a plain run of 5 digits with no separator, a dropped or transposed digit is easy to miss by eye but produces a code that still reads as plausible — often pointing to a different département altogether. Catching that at data entry is cheaper than a parcel misrouted to the wrong region.
How this validator works
This tool checks that the input is exactly 5 digits with no letters, spaces, or punctuation — the format La Poste has used since the 1970s postal reform introduced département-based numbering — entirely in your browser, with nothing sent to a server.
What a pass doesn’t tell you
A code postal carries no check digit, so a correctly shaped 5-digit string is the most a client-side check can confirm — not that La Poste has actually assigned it to a real commune or that it matches the city name also entered on a form. Confirming that requires La Poste’s own postcode lookup.
Scope: format validation only — not address lookup, commune matching, or confirming a code is currently in use.
code postal FAQ
What do the first two digits of a French code postal mean?
They usually match the number of the département the address sits in — for example 75 for Paris or 13 for Bouches-du-Rhône (Marseille). It's a widely useful hint, but not an exact rule: some large cities split their département's number across arrondissements, and a handful of postcodes cross département lines for historical reasons.
Why do some French postcodes start with the same two digits but clearly describe different towns?
Because the last three digits are what actually pin down the commune or arrondissement — the first two only narrow things to a département, which can contain hundreds of towns. A code postal only becomes specific once all 5 digits are read together.
Does a correctly formatted code postal mean it actually exists?
No. This tool only confirms the string is 5 digits — it doesn't check the code against La Poste's actual list of assigned communes. Confirming a code postal is real requires La Poste's own postcode lookup.