Artificial Intelligence

What is Token (AI)?

Quick answer

The basic unit of text a language model reads and writes, usually a word, part of a word, or punctuation mark.

Token (AI), explained

Language models do not see text as letters or whole sentences. A tokenizer first splits input into tokens, which are common chunks of characters. A short English word is often one token, while a long or unusual word may be split into several. Numbers, code, and non-English text often use more tokens per word.

Tokens matter in practice because most AI services price usage per token and limit how many tokens a model can handle at once. For example, if you paste a long contract into a chatbot, both the contract and the reply count toward the token total, which affects cost and whether the whole document fits. Counting tokens before sending a large request helps teams estimate spending and avoid truncated answers.

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