The Sweden Postnummer Validator checks whether a Swedish postal code has the correct five-digit structure and maps it to the broad postal region it belongs to. It is a fast sanity check for e-commerce address forms and data cleaning — all in your browser.
How it works
A Swedish postal code is exactly five digits, conventionally written as
NNN NN. The leading digits encode geography: the first digit identifies a
broad region and the first two digits narrow it further. Codes never begin with
zero.
The tool strips any space, confirms the value is five digits, and rejects a leading zero. It then reads the first two digits and maps them to a region using PostNord’s national numbering plan — for example the 10–19 range covers Stockholm, 40–47 covers Gothenburg and Västra Götaland, 20–29 covers Malmö and Skåne, and 90–99 covers the far north. The result is the formatted code plus its mapped region.
Example
The code 11330 is formatted as 113 30 and mapped to the Stockholm city and
inner region. A value like 01230 is rejected because Swedish codes do not start
with zero, and a four-digit value is rejected for the wrong length.
Notes
The region is derived from the leading digits and is approximate — real delivery areas are finer-grained and reassigned over time by PostNord, so a valid format does not guarantee the code is currently in use for delivery. Pair this with a full address lookup when accuracy matters. Everything runs locally in your browser.