Is there a way to count tokens for free?
Free token counting methods
For OpenAI models, the tiktoken Python library is free and open-source. You can install it and count tokens locally for GPT-3.5, GPT-4, and newer models. Anthropic provides a free token counting API endpoint that returns the token count without generating a response. Google offers a count_tokens method in its SDK.
There are also many free online tokenizer tools where you paste text and see the token count. These are handy for quick checks but may not support every model version. For accurate counts, use the official library or endpoint for your specific model.
Why counts vary by model
Different models use different tokenization schemes. A word like 'unbelievable' might be one token in one model and three in another. So a count from one tokenizer may not match another model's billing. Always use the tokenizer that matches your target model.
Token counts also include special tokens for message formatting, which can add a few tokens per message. Free libraries often account for this, but online tools may not.
- tiktoken (OpenAI) – free Python library.
- Anthropic token counting endpoint – free API call.
- Google count_tokens method – free in SDK.
- Hugging Face tokenizers – free for open models.
- Online tokenizer tools – quick but model-specific.
Common mistakes
- Assuming all models use the same tokenizer, so counts are interchangeable.
- Forgetting that special formatting tokens add to the total.
- Using an online tool that doesn't match your model version.
