Tokenizer visualizer
A playground for seeing exactly where the tokenizer draws its boundaries. Type below and your text is re-rendered with every token color-coded inline — hover any token to see its ID. Great for spotting why a word costs more tokens than you'd expect.
Tokenized
Hover a token to see its ID.
Colors mark token boundaries (alternating, so adjacent tokens are distinguishable). OpenAI counts are exact (o200k_base); other providers are estimates via the GPT tokenizer.
More free token tools
TokensToken counterPaste text, pick a model, and see exact tokens, characters, and chars/token — every token as a colored chip with its ID.CostLLM API cost calculatorReal token counts → dollar cost, split into input vs output, for the model you pick. Paste text to auto-count input.CostModel cost comparisonOne prompt + expected output length, costed side by side across every model in a sortable table.TokensContext window checkerPaste a prompt, pick a model, and find out whether it fits the context window — and how many tokens are left.TokensWord ↔ token estimatorQuick two-way converter between word count and token count, with real-tokenizer calibration.ExplainerFrom prompt to outputA clickable pipeline explaining how an LLM turns your prompt into output — tokenization, embeddings, transformer, sampling, and back.