Tokenizer Playground
Real-time tokenization with popular LLM models (GPT-4, GPT-3.5, GPT-5, Claude, Llama 2, BERT, T5). Experiment with different tokenizers, view token statistics, and estimate costs.
OpenAI GPT-4 and GPT-3.5 tokenizer (cl100k_base — accurate)
0
0
0
$0.0000
How to use:
- • Select a tokenizer from the dropdown (GPT-4, Claude, Llama 2, etc.)
- • Type or paste text in the input field to see real-time tokenization
- • View token statistics including count, characters, words, and estimated cost
- • Switch between Text, Token IDs, or Hide display modes
- • Copy tokenized text to clipboard or export results as JSON
Accuracy Notes
- • GPT-4, GPT-3.5, GPT-5, Claude: Token counts use the real cl100k_base tokenizer — accurate for GPT-4 and a very close approximation for Claude.
- • Llama 2, BERT, T5: These use simplified approximations. A browser-compatible SentencePiece/WordPiece library is not available; counts may differ from the real model.
- • Cost estimates are based on typical published pricing and may not reflect current rates.
❓Tokenizer Playground FAQ
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