tr -dc 'a-zA-Z0-9'

Category: Text Processing

tr -dc 'a-zA-Z0-9'

Delete all characters except alphanumerics

Keeps only letters and numbers, deleting everything else. -d means 'delete', -c means 'complement' (invert the set), so -dc keeps the set instead.
Looking for more? Search all 7,657 commands — works offline, in English or Spanish, and fixes typos.