Claude Token Counter — Count Tokens & Estimate Anthropic API Cost
Claude Token Counter is a free, browser-based developer tool that estimates token counts for Anthropic's Claude Opus, Sonnet and Haiku models and forecasts API costs in real time. Unlike word-based counters, it calibrates counts on Claude's known tokenizer behavior and works entirely in your browser: no uploads, no API keys, no sign-up. It is one of 90+ models covered by TokenCalc, a free AI token calculator for developers.
→ Open the Claude token counter — paste any prompt or document, get token counts and cost estimates for every Claude model in seconds.
Claude pricing (2026)
| Model | Token count | Input / 1M tokens | Output / 1M tokens | Context window |
|---|---|---|---|---|
| Claude Opus 5 | estimate | $5.00 | $25.00 | 200K |
| Claude Sonnet 5 | estimate | $2.00 | $10.00 | 200K |
| Claude Haiku 4.5 | estimate | $1.00 | $5.00 | 200K |
| Claude Opus 4 / Sonnet 4 | estimate | $15.00 / $3.00 | $75.00 / $15.00 | 200K |
Claude token counter by the numbers
- 90+ LLM tokenizers supported in one free tool
- 200K token context window on Claude Opus 5 and Sonnet 5
- 1.25 average tokens per English word
- $5.00 / $25.00 per 1M input / output tokens for Claude Opus 5
- 100% in-browser — your text never leaves the device
- 0 uploads, 0 API keys, 0 cost
How many tokens is a word in Claude?
One English word averages ~1.25 tokens (roughly 4 characters per token). Just like OpenAI's tokenizers, Claude's uses Byte-Pair-Encoding, so the exact ratio depends on your text:
- Common short words are often a single token.
- Long or technical words split into several tokens.
- Code and special characters tokenize more densely than prose.
- Chinese text runs ~0.6–1.2 tokens per character.
Why count Claude tokens?
Anthropic bills by tokens and Claude's context window is 200K tokens. Without an accurate count you risk:
- Oversized prompts — a document that doesn't fit the 200K window gets truncated or rejected.
- Surprise invoices — output tokens on Opus 5 cost $25 per 1M, so long generations add up fast.
- Model mismatch — the same text tokenizes differently between Claude, GPT-5 and Gemini; the cheapest model for a job isn't always obvious.
Claude token counter — free and private
Our AI Token Calculator covers Claude Opus, Sonnet and Haiku with proven estimates, plus exact token counts for GPT-5, GPT-4o, o1, o3 (official tiktoken) and 90+ more models — all in your browser, no upload, no API key.
→ Open the Claude token counter (free, private)
Claude token FAQs
How many tokens does Claude have per word?
About 1.25 tokens per English word, or ~4 characters per token. Always verify with a counter — the ratio varies with vocabulary and code content.
Is the Claude token count exact?
Claude counts are estimates calibrated on Anthropic's tokenizer behavior. OpenAI model counts are exact (official tiktoken). Estimates are accurate enough for budgeting and cost forecasting.
Does the Claude token counter upload my text?
No. Everything runs in your browser. Your text is never sent to any server.
What is a token in Claude?
A token is the smallest unit of text Claude's tokenizer processes — roughly one English word equals 1.25 tokens. Claude's 200K context window is measured in tokens, so an accurate count tells you how much text fits in a prompt.
How does the Claude token counter compare to Anthropic's own API?
Anthropic does not ship an offline, browser-runnable tokenizer. Our counter uses a proven estimate calibrated on Claude's token behavior — accurate enough for context budgeting and cost forecasting, while OpenAI models on the same tool return exact official counts.