How is the PPSN check letter calculated?

The seven digits are weighted by 8, 7, 6, 5, 4, 3 and 2. If a second letter is present, its A=1..Z=26 value times 9 is added. The total is reduced modulo 23; a remainder of 0 maps to W, otherwise the remainder selects the letter A-V. That letter must equal the 8th character.

Does a valid result mean the PPSN really exists?

No. The tool only confirms the format and modulo-23 check letter are correct. A structurally valid PPSN is not necessarily one that has been assigned, and it is never checked against any government register.

Is my PPS number sent anywhere?

No. The validator is privacy-first — all processing happens locally in your browser and the number never leaves your device.

Ireland PPS Number Validator

Validate an Irish PPS number using the modulo-23 check letter.

Ireland PPS number validator

Validate an Irish PPS Number (Personal Public Service Number). The format is 7 digits + a check letter, with an optional second letter introduced in 2013. The tool recomputes the modulo-23 check letter and compares it, including the second-letter contribution when present.

It is privacy-first: nothing leaves your browser. The validator only checks the format and check letter — it does not verify the number against any register.