The frontier model just became a mid-tier price point. anthropic's claude opus 5.5, released on…
the frontier model just became a mid-tier price point. anthropic's claude opus 5.5, released on september 22, matches the flagship fable 5.1 on most work while costing 40 percent less to run, scoring 57.8 percent on cursorbench 4.0 against fable's 51.8 and completing a 680,000-line code migration in a single pass.
the expensive model is now the one you keep for emergencies.
Context
Verified source: Anthropic's Sep 22, 2026 announcement introduces Claude Opus 5.5, and says one tester completed a 680,000-line code migration in less than a day. Anthropic's model docs price it at $4 per million input and $20 per million output tokens. llm-stats reports CursorBench 57.8% and says it is self-reported, and about 40% cheaper than Opus 5 at default.
The Sep 22 release, the 680,000-line migration and the 57.8% CursorBench score match Anthropic and llm-stats. The 680,000 lines was one tester's report and took less than a day, not 'a single pass'. llm-stats puts the 40% saving against Opus 5, while the post says against Fable 5.1, and VentureBeat's headline says a 60% cheaper API price against it. Fable's 51.8% on CursorBench was not seen in the sources read, so unsupported here, not refuted. in the excerpts read, and CursorBench is reported by llm-stats as self-reported. 'The expensive model is for emergencies' is the author's opinion.
Related work
- Claude Opus 5.5, Claude Docs ↗Pricing and breaking changes.
Watch next
- Read the VentureBeat piece for the price comparison against Fable 5.1.
Sources
- Introducing Claude Opus 5.5, Anthropicanthropic.com
- Claude Opus 5.5 overview, Claude Docsplatform.claude.com
- Anthropic releases Claude Opus 5.5, beating Fable 5.1, VentureBeatventurebeat.com
- Claude Opus 5.5: Fable-Class Work, Cheaper to Run, llm-statsllm-stats.com
Provenance
The note above is reproduced unedited from the original post, first published on Threads on 24 September 2026 at 20:52 IST. Sources are the papers and datasets the note draws on.
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