Count Tokens for Any AI Model. Instantly. For Free.
Estimate API costs, compare context window limits, and optimize your prompts. Powered by official tokenizers — 100% accurate, 100% private in your browser.
AI Model Token Limits Comparison
Compare context window sizes, max output tokens, and tokenizers across the most popular AI models
| Model | Provider | Context Window | Max Output | Tokenizer |
|---|---|---|---|---|
| GPT-5 | OpenAI | 256,000 | 32,000 | o200k_base |
| GPT-4o | OpenAI | 128,000 | 16,384 | o200k_base |
| GPT-4o mini | OpenAI | 128,000 | 16,384 | o200k_base |
| Claude Opus 4 | Anthropic | 200,000 | 32,000 | Claude |
| Claude Sonnet 4 | Anthropic | 200,000 | 16,000 | Claude |
| Gemini 2.5 Pro | 1,000,000 | 65,536 | Gemini | |
| Gemini 2.0 Flash | 1,000,000 | 8,192 | Gemini | |
| Llama 4 Maverick | Meta | 1,000,000 | 32,000 | Llama |
| DeepSeek-V3 | DeepSeek | 128,000 | 8,192 | DeepSeek |
Token limits are subject to change. Last updated: February 2026.
Why Use Our Token Counter?
Everything you need to manage token usage across different AI models and providers
Get instant token counts as you type or paste your text. No waiting, no server round-trips.
Count tokens for GPT-5, GPT-4o, Claude 4, Claude 3.5 Sonnet, Gemini 3 Pro, Llama 4, and more.
Estimate API costs per request based on the latest pricing for each model and provider.
Compare context window sizes and token limits across models to choose the best fit for your use case.
Powered by official tokenizers (tiktoken, etc.) for 100% accuracy matching actual API token counts.
All processing happens in your browser. Your prompts and data never leave your device.
How Token Counting Works
Understanding the tokenization process for AI language models
Paste Your Text
Paste or type your prompt, code, or any text content into the token counter. Select the AI model you want to count tokens for.
Tokenization
The text is processed locally using the official tokenizer for your selected model (e.g., tiktoken for GPT-5/GPT-4o, Claude tokenizer for Anthropic models).
Get Results
Get your token count, character count, word count, and estimated API cost instantly. Compare against the model's context window limit.
Frequently Asked Questions
Everything you need to know about token counting for AI models
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No registration, no limits, no hidden costs. Use our token counter as much as you need for personal or commercial projects.
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Always Up-to-Date
We regularly update our token counter with the latest AI models including GPT-5, Claude 4, Gemini 3, and use official tokenization libraries for 100% accuracy.