Observed arrival · 2026-10-05

Math Errata: A ledger for textbook mistakes

matherrata.org Visit website

Editorial interest 72/100 Selection signal · not a rating of the site

A community-maintained catalog for recording and investigating errors in mathematical textbooks.

Landing page captured for the 2026-10-05 issue.

For: Readers checking mathematical textbook editions
Worth noticing: Reports distinguish unreviewed suspicions from community-confirmed errors, author-confirmed corrections, and cases where the book is right.

Field notes

The catalog currently lists mathematical titles from abstract algebra, algebraic geometry, number theory, and topology, but each displayed book has zero reports and the activity section is empty. Its status labels distinguish an initial suspicion from ongoing investigation and settled outcomes, including cases where the report is withdrawn or the book is correct. The site says account holders can add books and editions.

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