Claude opus 5 shipped with thinking on by default, a 1m context, and the exact same price as opus…
claude opus 5 shipped with thinking on by default, a 1m context, and the exact same price as opus 4.8. flagships can no longer charge for the upgrade — the price war made the new model a free update.
the era of paying more per token for intelligence is done.
Context
Anthropic's Opus 5 page, with a search-metadata date of 24 July 2026, says it is priced at 5 dollars per million input tokens and 25 dollars per million output tokens, the same as Opus 4.8. The model overview lists a 1M-token context window and 128K max output, and the prompting guide says Claude Opus 5 runs with thinking on by default, which can be disabled only at effort high or below.
The docs pages are current docs, not release-date evidence. The same overview table now also lists Claude Opus 5.5 at 4 and 20 dollars and Claude Fable 5.1 at 10 and 50 dollars, so the model-name claims hold but the conclusion that a flagship cannot charge more is not supported by that table; that is current docs, not a dated comparison. Anthropic says Opus 5 comes close to Fable 5's intelligence at half the price. The era of paying more per token being over is the author's opinion.
Related work
- Prompting Claude Opus 5 (Claude docs) ↗First-party.
Watch next
- Anthropic pricing changes and migration notices.
Sources
- Claude Opus 5 (Anthropic)anthropic.com
- Opus 5 overview (Claude docs)platform.claude.com
Provenance
The note above is reproduced unedited from the original post, first published on Threads on 18 September 2026 at 05:17 IST. Sources are the papers and datasets the note draws on.
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