Definition
Token
A token is a unit of text or data that a language model processes, often a word part, word, punctuation mark, or symbol. Tokens determine context limits, pricing, latency, and how much information can be read or generated in one request.
Last updated: 25 June 2026
Why it matters
Token counts quietly drive AI cost and can explain why long prompts become slow, expensive, or incomplete.
Signals to watch
- Prompts have length limits
- Vendors bill by token
- Long documents are split before processing