LLM Token Counter

What is LLM Token Counter?

LLM Token Counter counts the number of tokens in your text using the same tokenization algorithm (cl100k_base) used by GPT-4 and other large language models. See real-time token counts, estimated API costs, and context window usage — all without sending your prompts to any server.

How to Use

1. Paste or type your text into the input area
2. Select the LLM model to see model-specific costs and context limits
3. View the token count, estimated cost, and context window usage in real time
4. Toggle token visualization to see how your text is split into tokens

Use Cases

• Estimating API costs before sending prompts to GPT-4 or Claude
• Checking if prompts fit within context window limits
• Optimizing prompt engineering by reducing token count
• Understanding how different text formats affect tokenization

Privacy & Security

All tokenization happens entirely in your browser. Your prompts, API calls, and sensitive data are never sent to any server — which is exactly how a token counter for LLM prompts should work.