A token is a small piece of text an AI computes with, often part of a word. AI vendors set prices and limits in tokens.
Illustration: AI-generated · AI Compare Ninja · CC BY 4.0
Example
The word “unbelievable” is split into several tokens internally.
For pros
As a rough rule, one English token is about three quarters of a word; other languages often need more tokens. APIs usually price input and output tokens differently.
