Family · Anthropic
Claude Sonnet
Claude Sonnet is a model family from Anthropic. We track 2 versions: Claude Sonnet 5 and Claude Sonnet 4.6. Claude Sonnet 5 is the version we would evaluate first, and older versions stay listed so you can compare price and capability before deciding whether to move.
Comparing Claude Sonnet 5 with Claude Sonnet 4.6: Claude Sonnet 5 is listed at API: $2 in / $10 out per M tokens, while Claude Sonnet 4.6 is listed at API: $3 in / $15 out per M tokens. Newer versions usually improve reasoning, tool use and price, so unless you depend on the exact behavior of an older model, evaluate the newest version first and keep the older one only as a fallback.
Version comparison
| Version | Pricing | Free tier | Last reviewed | |
|---|---|---|---|---|
| Claude Sonnet 5 | API: $2 in / $10 out per M tokens | No | Sep 2026 | Read review → |
| Claude Sonnet 4.6 | API: $3 in / $15 out per M tokens | No | Sep 2026 | Read review → |
All Claude Sonnet versions
Claude Sonnet 5 is the mid-tier model in the Claude 5 family and the default choice for most professional work. Anthropic made its launch pricing of $2 and $10 per million tokens permanent, which makes it one of the best price-to-quality options in the lineup.
Strength: Lower price than Sonnet 4.6 with newer capabilities Limit: Below Opus on the hardest reasoning tasks
Claude Sonnet 4.6 is the previous mid-tier Claude model, priced at $3 and $15 per million tokens. Sonnet 5 now costs less and is the better choice for new work, but 4.6 remains available for teams that need its established behavior.
Strength: Reliable everyday performance Limit: Costs more than Sonnet 5
Frequently asked questions
Which Claude Sonnet version should I use?
Claude Sonnet 5 is the newest version we treat as current. Claude Sonnet 5 is the mid-tier model in the Claude 5 family and the default choice for most professional work.
Are older Claude Sonnet versions still available?
Many stay available through the vendor API or partner clouds for a while, but newer versions are usually cheaper or stronger. Each older version's page notes what replaced it.
How do Claude Sonnet versions differ on price?
Claude Sonnet 5: API: $2 in / $10 out per M tokens. Claude Sonnet 4.6: API: $3 in / $15 out per M tokens.