# TestingCatalog — Anthropic launches Claude Opus 5.5 with lower API costs

- Company: TestingCatalog (testingcatalog.com)
- Announced: 2026-09-22T20:41:24+00:00
- Category: new-model
- Coverage: not counted
- Announcement: yes
- Group: models
- Source: https://www.testingcatalog.com/anthropic-launches-claude-opus-5-5-with-lower-api-costs/
- Record: https://forck.live/items/13124-anthropic-launches-claude-opus-5-5-with-lower-api-costs
- Subject: AI models / agents / unreleased features
- Models affected: Claude Opus 5.5, Opus 5, Claude Fable 5.1, Claude Mythos 5.1, Claude Sonnet 5.5, Claude Haiku 5.5, GPT-6 Astra, GPT-5.6 Sol, Opus 4.8
- Pricing: API pricing is $4 per million input tokens and $20 per million output tokens, compared with $5 and $25 for Opus 5. Cache reads cost $0.20 per million tokens and writes cost $5. Fast mode in Claude Code and the Claude Platform reaches up to 2.5 times the speed for $8 per million input tokens and $40 per million output tokens.

Anthropic released Claude Opus 5.5, the first model in the Claude 5.5 family, available via Anthropic, AWS, Google Cloud, and Azure. The model matches Claude Fable 5.1's performance on most tasks while costing 40% less to run than Opus 5 on typical workloads, with API pricing at $4 per million input tokens and $20 per million output tokens. It also generates output more than 30% faster than Opus 5 at default settings and includes safety features such as a pre-execution action classifier, an open-source sandbox, and preserved thinking.

## Evidence

Verbatim from https://www.testingcatalog.com/anthropic-launches-claude-opus-5-5-with-lower-api-costs/:

> It performs at the level of Claude Fable 5.1 for most tasks, and costs 40% less to run than Opus 5.

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