Claude Fable 5.2 vs Opus 5.5: It Wins. Should You Switch?

In this article you will learn:

• where Fable 5.2 beats Opus 5.5 in the benchmarks, and the one result where it doesn't
• what it costs, and how much of it your Claude plan includes
• how I'm going to test it against Opus 5.5 on my own work

Quick answer

• Claude Fable 5.2 came out on November 9, 2026. In the benchmarks Anthropic published, it is ahead of Opus 5.5 in 11 of 12 results.
• It costs twice as much per token as Opus 5.5: $8 per million input tokens and $40 per million output tokens. That is still 20% less than Fable 5.1.
• Max and Ultra include it, up to 50% of the weekly limit. Pro includes it only until November 16. After that, it runs on usage credits again.
• Anthropic still recommends Opus 5.5 for everyday work. Fable is meant for the hardest tasks.
• Is it worth switching? That depends on the cost of a finished task, not of a token. I don't know that number yet, so I'm going to measure it.

Fable 5.2 vs Opus 5.5 in the benchmarks

Anthropic's announcement comes with a table of 14 benchmarks. Three of them show only Mythos 5.2: the same model without the cybersecurity and biology safeguards, open to vetted organizations only. The other eleven give twelve results (one benchmark is scored in two ways), and compare Fable 5.2 with Opus 5.5, Fable 5.1, GPT-6 Astra and Gemini 4 Carbon.

Pick the rival:

What I take from it:

• In coding, it is ahead, but not by a mile. 49.1% vs 45.5% on FrontierCode 2.0, and 69.9% vs 62.3% on FrontierSWE v2.
• The big gaps are in long, open-ended work. On the Remote Labor Index, Fable 5.2 nearly doubles Opus 5.5: 41.3% vs 21.3%. That is the kind of work Anthropic says Fable is for.
• Opus 5.5 wins one. AA-Briefcase, a knowledge-work benchmark, gives two scores. Fable has the higher rubric score, but Opus has the higher Elo rating: 1800 to 1785. That is a gap, but marginal in my eyes.
• Against Fable 5.1, it is a different league. From 32.4% to 49.1% on FrontierCode, and from 17.9% to 41.3% on the Remote Labor Index. It is also up to 30% faster.
• GPT-6 Astra leads nowhere, Gemini 4 Carbon leads once: on AutomationBench, 53.9% to 51.4%.

Take it with a grain of salt, though. These are Anthropic's own numbers, with each model at its highest effort. That is not what you get by default: Claude Code and the Claude apps start at Medium.

What Fable 5.2 costs

Prices per million tokens, from Claude's pricing page:

There is also a fast mode: up to 2.5 times faster output, for twice the price ($16 and $80).

So a token from Fable costs twice as much as a token from Opus. But the announcement makes a more interesting claim, about the cost of a task:

• On FrontierCode, Fable 5.2 at High effort scores about the same as Opus 5.5 at its best (45.3% vs 45.5%) "for roughly half the cost per task".
• On WANDR, an agentic search benchmark, Fable 5.2 at Medium effort matches Opus 5.5's top score "for about 40% of the cost per task".

If that holds on my work, the model with the double price tag is the cheaper one. That's a big "if" 😅

How much Fable does your Claude plan include?

This part is easy to get wrong, because it changed more than once this year. As of today:

Both come from Claude's help center: Fable models on your plan and the launch offers. Three things are worth knowing:

• The 50% is a cap, not a bonus. Fable and the other models draw from the same weekly limit. When Fable has taken half of it, you switch to another model or pay with usage credits.
• Fable burns the limit faster. "Fable models use your usage limits faster than other Claude models", says Anthropic - without saying how much faster.
• A Fable reset gives back what you spent on Fable in the weekly limit, and refills the 5-hour window. You get one if you have subscribed for less than six months, two for six to twelve months, three for more than a year.

I have both: a Max plan and a Pro plan. So on Pro I have one week to play with it, and on Max at most half of every week.

Should you switch from Opus 5.5?

Anthropic's own answer is no:

For most coding and knowledge tasks, we recommend that users start with Claude Opus 5.5, our strongest daily driver, and then switch to a different model as required.

That's how I have worked so far. Since September 25, when I started pricing my usage at API rates, 93% of it went to Opus 5.5. Before launch day, I hadn't sent a single request to a Fable model.

Whether that should change comes down to one number I don't have: how much of my limit a task takes on Fable, compared to the same task on Opus. Twice the price per token doesn't answer it, because Fable may need fewer tokens to finish. Or more.

The 50% cap limits how much there is to win or lose. Try it:

In the worst case here, half of the week on Fable means 25% less done. If Anthropic's FrontierCode figure holds for me, it means 50% more. And the chart counts only how much gets done, not how well - while "how well" is the whole reason to pay for a stronger model.

How I'm going to test it

1. The same task on both models. Real tasks from my projects, with the same prompt and the same starting commit.
2. Cost per task, not per token. My usage dashboard prices every request at API rates and tracks the weekly limit. So I'll see each task in dollars and in percent of the limit.
3. A blind review. Codex reviews both results without knowing which model wrote which. I count how many times I had to correct each model.
4. Effort levels. Fable at Medium and at High, against Opus the way I run it every day.
5. Fable as the planner. Fable plans and reviews, Opus builds.

Final thoughts

• On paper, Fable 5.2 is the better model. 11 of 12 is not a close call.
• The price per token is the wrong number to stare at. What decides is the cost of a finished task, and nobody will measure that for you.
• The 50% cap makes the choice smaller than "switch or stay". At most half of the week can go to Fable, so the real question is which tasks deserve it.
• If you are on Pro, you have until November 16 to find out without paying extra.

I hope this was a meaningful read - if so, let me know in the comments. And if you have already run Fable 5.2 against Opus 5.5 on your own work, tell me what you saw :)

What's next

The results of that test. See you there!

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