Anthropic’s product page, dated September 22, 2026, introduces Claude Opus 5.5 as “the first model in our new Claude 5.5 family”. Anthropic says it performs at roughly the level of Claude Fable 5.1 on most work and costs 40% less to run than Opus 5. It says Sonnet 5.5 and Haiku 5.5 would follow, and both did: see Sonnet 5.5 and Haiku 5.5.
What to know
- Anthropic lists standard prices per million tokens of $4 for input and $20 for output (Opus 5 was $5 and $25). Fast mode, up to 2.5x speed in Claude Code and the Claude Platform, is $8 and $40.
- The model ID is
claude-opus-5-5. Anthropic says it is available on all platforms, including Amazon Web Services, Google Cloud and Microsoft Azure, with zero data retention. - Anthropic reports 66.4% on Terminal-Bench 4.0 (Opus 5: 52.3%) and 1846 Elo on GDPval-AA v2.1 (Opus 5: 1708). Anthropic itself notes that benchmark margins are a less reliable guide at this capability level.
- Thinking cannot be switched off.
- Safeguards: biology use is subject to the same safeguards as Fable 5.1, and cybersecurity tasks are partly routed to Claude Opus 4.8. Anthropic says expanded access for verified cyberdefenders is planned.
- Anthropic says it is raising five-hour usage limits on Pro, Max, Team and seat-based Enterprise plans.
Why it matters
It moves the top Claude tier to a lower per-token price. If you chose between tiers, our Claude 5.5 model chooser guide compares all three, and the Claude tool page has the full lineup.
Disclosure: Anthropic’s Claude is one of the tools used to help build this site. We cover Claude models on the same basis as every other maker.
Source: Anthropic. We summarise in our own words; check the source for the full details.