Grok Token Counter
Estimate tokens before sending your prompt to xAI Grok 3, Grok 3 Mini, or Grok 4. Useful both for the X consumer UI and for the developer API on api.x.ai.
Keyword density
Top 8Add a prompt to see your top keywords.
Grok’s tokenizer
xAI uses a custom BPE tokenizer similar in spirit to OpenAI’s and Llama’s. For English text, density is roughly 4 characters per token — close enough to the ChatGPT estimate that this counter’s default heuristic works well as a sizing guide.
For exact counts, the xAI API returns token usage in every response under usage.prompt_tokens and usage.completion_tokens.
Grok context windows
| Model | Context window | Notes |
|---|---|---|
| Grok 3 Mini | 131K tokens | Fast, lower cost |
| Grok 3 | 131K tokens | Default for most workflows |
| Grok 4 | 256K tokens | Frontier reasoning + tools |
Real-time information
One thing that distinguishes Grok from other models is its tighter integration with live data — X posts, recent web pages, and breaking news. When you ask Grok a current-events question and it retrieves data, that retrieved text consumes additional tokens in your context window beyond what you typed. Budget accordingly when prompts involve real-time search.