claude-sonnet-5 — pricing, context window and limits

Near-Opus quality at Sonnet pricing

Sonnet 5 is built to close the gap between Sonnet and Opus specifically on coding and agentic work, at Sonnet's own price point rather than Opus's — and it's the first Sonnet generation to carry the second-highest effort tier at all, a capability previously exclusive to the Opus line.

Two migration traps worth checking before you move real traffic

The tokenizer here counts noticeably more tokens than the immediately prior Sonnet generation for identical text, at an unchanged sticker price — a real cost consideration invisible if you're only looking at the per-token rate. And thinking runs by default now, which it didn't on the prior generation, meaning max_tokens has to account for thinking overhead it previously didn't need to. See what actually changed from Sonnet 4.6 to Sonnet 5 for both in full.

A temporary introductory rate is active

This model currently carries a promotional per-token rate below its standard price, active for a limited window. See what changes when an intro price expires for what to budget for once that window closes.

Related

See migrating: Sonnet 4.6 to Sonnet 5 and Sonnet 5 vs Haiku 4.5 for how it stacks up against the lineup's cheaper option.