Check a list of postal codes

Paste a column of postal codes and check them against the country's real format. Useful before a bulk upload, a mail merge, or a shipping import.

Nothing leaves your browser. The check runs on this page using data already loaded here. No codes are uploaded, logged or stored — which matters, because these lists usually come out of a customer export.

What it checks

• Format — against the pattern that country actually uses, not a generic "5 digits" assumption.
• Existence — where we hold the country's codes, it says whether the code is one of them, and which place it belongs to.
• Lost leading zeros — the most common corruption there is. A spreadsheet turns Dresden's 01067 into 1067, which is not a valid German code at all. The checker spots the pattern and tells you the original.