Simon Willison’s Weblog

Hashids (via) Confusingly named because it’s not really a hash—this library (available in 40+ languages) offers a way to convert integer IDs to and from short strings of text based on a salt which, if kept secret, should help prevent people from deriving the IDs and using them to measure growth of your service. It works using a base62 alphabet that is shuffled using the salt.