These postcodes are structurally valid but fictional, for software testing and form design. This is not a Royal Mail postcode lookup: the Derby districts are real, the full postcodes are not assigned to any address.
A random Derby postcode generator combines a real Derby postcode district with a generated inward code, producing a structurally valid postcode that is not assigned to any delivery point.
Every postcode on this page starts from a genuine Derby postcode district. There are 6 of them, in the DE postcode area, and they all belong to the DERBY post town in Derbyshire. The three characters after the space are generated to the Royal Mail format rules, so a result validates in any form or database while belonging to no real property.
DE21 5QA — district DE21, sector DE21 5, DERBY, DerbyshireDE3 6LS — district DE3, sector DE3 6, DERBY, DerbyshireDE1 6UA — district DE1, sector DE1 6, DERBY, DerbyshireDE21 0JD — district DE21, sector DE21 0, DERBY, DerbyshireDE23 5LL — district DE23, sector DE23 5, DERBY, DerbyshireDE23 5YW — district DE23, sector DE23 5, DERBY, DerbyshireThis page produces postcodes on their own. For complete Derby addresses — building number, street, locality, post town, Derbyshire and postcode, laid out to Royal Mail conventions — use the random Derby address generator.
A UK postcode splits into an outward code and an inward code. The outward code identifies the district; the inward code narrows it to a small group of properties. This generator keeps the first half real and generates the second, which is what makes the output safe to use and still valid.
Derby sits in the DE postcode area. Every district below is a real outward code assigned to the DERBY post town.
| District | Locality | Structural range |
|---|---|---|
| DE1 | — | DE1 0AA – DE1 9ZZ |
| DE3 | Mickleover | DE3 0AA – DE3 9ZZ |
| DE21 | Chaddesden | DE21 0AA – DE21 9ZZ |
| DE22 | Allestree | DE22 0AA – DE22 9ZZ |
| DE23 | Littleover | DE23 0AA – DE23 9ZZ |
| DE24 | Alvaston | DE24 0AA – DE24 9ZZ |
The structural range is what the postcode grammar permits for each district, not a list of codes Royal Mail has issued. Which sectors and units are actually allocated is Postcode Address File data, which is licensed and not held here — so a generated postcode inside the range may well be unallocated. For test data that is the point.
A postcode carries more than a location. Reading one from Derby tells you which country's addressing conventions apply, which ceremonial county the address sits in, and — if you need a matching telephone number — which dialling code area it falls in.
| Field | Value | Where it comes from |
|---|---|---|
| Post town | DERBY | Royal Mail post town, written in capitals on the address |
| Postcode area | DE | The leading letters of every district above |
| Ceremonial county | Derbyshire | ONS administrative geography |
| Country | England | One of the four countries of the United Kingdom |
| Region | East Midlands | ONS ITL1 statistical region |
| Dialling code | 01332 | Ofcom National Telephone Numbering Plan |
Royal Mail has not required a county line on addressed mail since 1996. DERBY plus a correct postcode is sufficient; Derbyshire is included because plenty of address forms and legacy databases still expect a county.
What they are not for: sending post, verifying an identity, or implying that a property exists. If you need to know whether a Derby address is deliverable, that is a licensed Royal Mail Postcode Address File lookup, and no generator can answer it.
The districts are real: all 6 of them are Royal Mail outward codes genuinely assigned to the DERBY post town. The three characters after the space are generated, so the full postcode is almost certainly not allocated to any property. That combination is deliberate — the result resolves to Derby in a district lookup and passes validation, but it is not a live delivery point and must never be used to send post.
6, in the DE postcode area: DE1, DE3, DE21, DE22, DE23, DE24. That is the count for the DERBY post town as recorded in this site's registry; a post town does not follow council boundaries, so it may not match what a resident would call "Derby".
DE. The postcode area is the leading letter or letters of the outward code, so every Derby postcode begins DE — for example DE1. The digits that follow identify the district within the area.
This page generates postcodes on their own and explains Derby's district structure. The Derby address generator produces complete postal addresses — building number, street, locality, post town, county and postcode — laid out to Royal Mail conventions. Use this page when you need postcodes to test a postcode field; use the address generator when you need whole addresses.
Yes, with no API key. Call GET /api/v1/postcodes/random?location=derby&count=25 for JSON. Add &seed=1 to get the same set back on every request, which keeps snapshot tests stable. The response carries the outward code, inward code, area, district and sector for each postcode alongside the post town and county.
Structural validation, yes: the format, the length and the excluded letters are all respected, so a correctly written regex or a library check will accept them. A validator backed by licensed Postcode Address File data will reject most of them, correctly, because the full postcode is not an allocated delivery point. If your test suite needs addresses that pass a PAF lookup, no generator can supply them.
Postcodes are generated on demand and never stored. They are for software testing and development only, and must not be used to send post, to imply a real address, or for identity verification.