AI prompt tool
Count tokens before sending text to a model
Tokenizers
Token Counter check prompt and context budgets Tokenizer comparison
When token count matters
Prompts and documents
Use this for prompt drafts, pasted documents, transcript chunks and retrieval passages that need to fit inside a model context window.
Leave response room
A prompt can fit but still fail if it leaves no room for the answer. Use the budget meter as a practical guardrail rather than a hard quality score.
Token counter questions
What is a token in AI?
A token is the chunk of text that a language model reads and writes. Tokens are usually short word fragments, so a token count is not the same as a word or character count.
How many tokens fit in a model context window?
Context windows vary widely across models, from a few thousand tokens to over a million. Set the context limit above to match your target model and watch the budget meter as you add content.
How accurate are these token counts?
OpenAI tokenizer counts use the official tokenizer libraries and are exact. Counts for other providers are labeled as estimates because their tokenizers are not always public.
Should I count tokens or words for prompts?
Count tokens when the question is whether content fits in a context window or how much you will pay per request. Word counts are easier for editing but do not match what the model actually sees.