Token Counter
Free token counter and content length calculator. Estimate prompt tokens and string length locally in your browser with character, word, and byte counts. No upload, no account.
Runs locally in your browser. Your input is not uploaded to DevToolMate servers.
Approximate counts
Estimates blend character length (about 4 per token) and word count. Use for budgeting, not billing-exact counts.
Developer Quick Tips
- Paste your prompt to instantly calculate character count, word count, byte length, and approximate token estimate, all in your browser with no upload.
- Use approximate token counts for context window budgeting before sending prompts to OpenAI, Claude, or other LLM APIs.
- Token estimates blend character and word heuristics for planning; verify against your model's official tokenizer for billing-critical decisions.
- Calculate string length and content length for any text, not just prompts. Pair with Prompt Diff to compare how edits change content size.
- Press Ctrl or Cmd + Enter to calculate after pasting input.
Frequently asked questions
How does Token Counter estimate tokens?
Token Counter uses a blended heuristic that averages a ~4-characters-per-token estimate with a ~1.3-tokens-per-word estimate. This gives a practical middle ground for context window budgeting across most LLMs. It does not run model-specific tokenizers like tiktoken or cl100k_base.
Can I use this as a content length counter?
Yes. Token Counter reports character count (Unicode characters), word count (whitespace-separated), and UTF-8 byte length alongside approximate token estimates. Use it to calculate string length and content length for any text, not just prompts.
What's the difference between approximate tokens and actual token counts?
Token Counter estimates tokens locally using a blended heuristic. Actual token counts depend on the model's tokenizer (OpenAI's cl100k_base, Anthropic's tokenizer, etc.). Use approximate counts for context-window budgeting; use official tokenizers for billing and quota enforcement.
Does Token Counter work with OpenAI, Claude, and other models?
Token Counter uses a blended heuristic that approximates tokens across most LLMs. It does not run model-specific tokenizers. Use it for rough planning with any provider, but verify final counts against your model's official tokenizer before billing-critical decisions.
How do I calculate string length with Token Counter?
Paste your text into the input field and press Ctrl or Cmd + Enter. Token Counter instantly displays character count, word count, and byte length. This works for any string, whether you're counting prompt length or general text content.
Does Token Counter upload my data or require an account?
No. Token Counter runs entirely in your browser. Your input is never uploaded to DevToolMate servers or external APIs. No account required, completely free, and processing stays on your device for the current session.
Will my input be stored after I close the tab?
No. Input stays in memory while the page is open. Closing the tab clears it. Only your theme preference is stored locally in your browser, not your tool input.
Related tools
- Context Budget Splitter: Split long text into character-budget chunks for LLM context windows. Free browser tool, no upload. Estimate tokens locally.
- Prompt Diff: Compare two prompts line by line in your browser. Free, no upload. Private, browser-based developer tool.