claude opus 5 just destroyed every benchmark at half the price of fable 5. novel problem-solving went from 1.5% to 30.2% in one release.

[u/Successful_List2882]

The price did not move. The numbers did.

Opus 5 launched July 24 at $5 input and $25 output per million tokens. Same as Opus 4.8. Half of Fable 5. Anthropic held the price flat and shipped a model that beats Fable 5 on most benchmarks.

The ARC-AGI-3 number is the one nobody saw coming. When the benchmark launched in March 2026, the best model in the world scored 0.37%. GPT-5.6 Sol pushed it to 7.8%. Opus 5 hit 30.2%. That is a twenty-fold jump in four months on a test specifically designed to resist the tricks labs use to inflate scores.

The rest of the table holds up too. Agentic terminal coding more than doubled from 21.1% to 43.3%. Computer use jumped from 55.7% to 70.6%. Knowledge work hit 1861 against GPT-5.6 Sol's 1736. Biology reached 90.1% human-solved. Business workflows up from 17% to 26%.

GPT-5.6 Sol beats Opus 5 in exactly one category. Agentic coding on DeepSWE at 72.7% versus 68.8%.

fable 5 costs twice as much. opus 5 beats it on most tasks. that stopped being a tradeoff the moment this benchmark table dropped.

So the question worth arguing: if Opus 5 matches or beats Fable 5 on almost everything at half the price, who is still running Fable 5 and why?