SEDOL Validator

How to use

1. 1Choose a mode: Validate SEDOL for a single code, Batch list for many, Check digit to complete a body, or SEDOL to ISIN to convert.
2. 2In Validate mode, type or paste a 7-character SEDOL; spaces and dashes are ignored and letters are upper-cased automatically.
3. 3Read the verdict, the per-character weighting table, and, if the check digit is wrong, the corrected SEDOL.
4. 4Use Batch mode to paste a column of SEDOLs, see valid and invalid counts, and copy only the valid ones.
5. 5Use Check digit mode to enter the first six characters and get the seventh check digit and the completed code.
6. 6Use SEDOL to ISIN mode to build the GB and IE ISIN from a SEDOL, then copy whichever you need.

About this tool

SEDOL Validator checks a Stock Exchange Daily Official List code the way a securities master or fund-administration system does, entirely in your browser. A SEDOL is the 7-character identifier the London Stock Exchange assigns to securities traded in the United Kingdom and Ireland: a 6-character body plus a single check digit. The check digit is what this tool verifies and computes. Each character has a value, where a digit is its own value and a letter is its alphabet position plus nine (B is 11, C is 12, up to Z is 35); the seven positions carry the fixed weights 1, 3, 1, 7, 3, 9, 1; the products are summed; and a valid code is one whose total is a multiple of 10. Two rules trip people up and the tool checks both: SEDOLs issued before 26 January 2004 are all digits, while every SEDOL issued since is alphanumeric, and vowels (A, E, I, O, U) are never used, which is why the letter A and its value of 10 never appear. Validate mode takes a single SEDOL, cleans away spaces and dashes, upper-cases it, and reports a clear pass or fail with the full weighting table, so you can see exactly how the check digit was derived; when the check digit is wrong it shows the digit that should be there and the corrected code, turning a single typo into a one-glance fix. Batch mode runs the same checks over a whole column of SEDOLs pasted from a spreadsheet, ticket, or export, counts how many pass, flags the reason each failure failed, and lets you copy just the valid ones. Check digit mode takes only the six-character body and returns the seventh digit, completing a code you are constructing. SEDOL to ISIN mode builds the matching UK and Ireland ISINs, because a GB or IE ISIN is the country code followed by the SEDOL right-padded with two leading zeros to nine characters and a final ISIN Luhn check digit; it also tells you whether the source SEDOL's own check digit was valid first. This is useful for fintech and trading-system developers, fund and back-office operations, data-quality and reconciliation work, and anyone cleaning a securities reference file. One honest scope note: a passing result proves the code is well formed and its check digit is correct, not that the security exists or is currently listed, which only a securities reference database can confirm. All validation and math run locally, so the codes you paste are never uploaded, logged, or sent anywhere.

Free to use. Works in your browser. No signup, no login.