Data Quality

Validate Values Against a Standard

One value per line, checked against the validator you choose, with check digits verified and personal identifiers masked.

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Processing happens locally in your browser. What you paste or load is processed by this page and is not uploaded to a server. Nothing is stored unless you use a control that says it stores something, and you can clear anything this site has kept from the privacy page.

Every validator, with what it checks and a test box, is in the validation library.

How to use this tool

  1. Choose the validator — an email address, an IBAN, a national identifier, a postcode.
  2. Paste the values, one per line, or upload a text file.
  3. Select Validate.
  4. Read the reason beside each invalid value; it names the part of the standard the value breaks.

What value validator does

Most format checks stop at the shape: an email has an at sign, an IBAN starts with two letters. That is how a mistyped account number reaches a payment run — it has the right shape and the wrong check digits. The validators here go as far as the standard does, so an IBAN is verified with its mod-97 checksum, a card number with its Luhn digit, and a national identifier with whatever check its issuing authority defines.

Each line is judged on its own, and the result says why a value failed rather than only that it did. Validators that deal with personal identifiers mask the values they show, so the result is safe to screenshot. Failures are flagged and nothing is changed: whether a bad value should be rejected, fixed or kept is a decision about your data that a checker is not entitled to make.

Frequently asked questions

No. A valid result means the value is well formed and its check digits are right, which rules out most typing mistakes. Whether the IBAN is an open account, or the tax number was issued to the person on your record, can only be answered by the system that issued it.

Validators for national identifiers, card numbers and similar personal data treat the value as sensitive, so the result shows only enough of it to find the line. The check itself runs on the full value, in this page, and nothing is sent anywhere.

A blank line is neither valid nor invalid; it is counted separately, because an empty value is a completeness question rather than a format one. A value the validator could not evaluate for another reason is reported the same way, with the reason.

Validators that need a parameter, such as a pattern or a list of allowed values, are on the validation library page, which has a form for them. This page offers the ones that work with their defaults.