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Token calculator

Paste text to estimate its token count, then pick any of 338 models to see what sending it would cost. Prices include the flat 3% fee — the receipt shows the provider price beside it.

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Est. tokens

Estimated at ~4 characters per token (English). Actual counts vary by tokenizer, typically within ±15%.

Estimated costopenkey.ai

anthropic/claude-sonnet-4.5

EST. TOKENS0

As input · $3.09/1M$0.00

As output · $15.45/1M$0.00

Per 1M tokens: $3.00 + 3% = $3.09 in · $15.00 + 3% = $15.45 out — flat 3% fee included

What a token is

Models don't read words — they read tokens, short chunks of text produced by a tokenizer. Common English words are usually one token; longer or rarer words get split into pieces. In English text, one token works out to roughly 4 characters, or about three-quarters of a word. Every model family uses its own tokenizer, so the same text produces different counts on different models — which is why this calculator gives an estimate, typically within ±15% of the real count.

Why prices are per 1M tokens

A single token costs a fraction of a hundredth of a cent, so per-token prices would be unreadable rows of zeros. Quoting per 1M tokens keeps the numbers comparable at a glance. At $3.09 per 1M input tokens, sending a 500-word email (≈667 tokens) through Claude Sonnet 4.5 costs about $0.0021. You're billed for input tokens (what you send) and output tokens (what the model writes back) at separate rates — output usually costs more.

Rough conversions

1 token
≈ 4 characters · ≈ 0.75 words
100 words
≈ 133 tokens
1 page (500 words)
≈ 667 tokens
1M tokens
≈ 750,000 words · ≈ 1,500 pages

English-language approximations — code, other languages, and unusual formatting tokenize differently.

Keep going

Now send those tokens somewhere.

One OpenAI-compatible key for all 338 models, each at its provider price plus 3%.