🔗 OpenRefine
This bookmark is very old and the link may no longer work. Try this archived link from the Internet Archive:
🗃️ https://web.archive.org/web/*/https://openrefine.org/
OpenRefine is a powerful free, open source tool for working with messy data: cleaning it; transforming it from one format into another; and extending it with web services and external data.
(Originally Google Refine)