Claude Sonnet 5.5 costs $6.43 per million words.
Anthropic lists it at $2 per million input tokens and $10 per million output tokens on Anthropic’s pricing page, read 4:40 PM Eastern, Oct 7, 2026. It bills about 1,608 tokens for a thousand English words, so a million words, three in for every one out, costs $6.43.
- Maker
- Anthropic
- Input
- $2 per million tokens
- Output
- $10 per million tokens
- Cached input
- $0.20 per million tokens
- Tokens for 1,000 words
- 1,608, measured by Brass on Oct 7, 2026
- Source
- Anthropic’s pricing page
In the Brass chat it costs $2.50 in and $12.50 out per million tokens, the list price Brass pays plus 25%, shown on every receipt.
Price history
| From | Per million words | Per million tokens, in / out |
|---|---|---|
| Oct 7, 2026 | $6.43 | $2 / $10 |
We began tracking Claude Sonnet 5.5 on Oct 7, 2026.