AI in public

AI in public

Opus 5.5: I Tested This Model on Real Work

Opus 5.5 Costs 40% Less Than Opus 5. Is It Actually Better? I Tested Both

Hamza Khalid's avatar
Hamza Khalid
Sep 25, 2026
∙ Paid

You’ve been rationing Fable.

I know because I’ve been doing it too.

I wrote a whole issue on how to stop hitting Fable usage limits.

The best model was always the one you could only afford to use a few times a day.

On September 22, Anthropic released Claude Opus 5.5.

It isn’t a Fable update or a new top tier.

It’s the Opus model, the one that sits below Fable.

On Anthropic’s own benchmark table, it beat Fable 5.1 in every row.

X avatar for @ClaudeDevs
ClaudeDevs@ClaudeDevs
If you're on Pro, Max, or Team, your reset is available today in Settings → Usage. Apply it any time until Oct 22. Opus 5.5 is the default for paid plans. It's priced lower than Opus 5, so your 5-hour and weekly limits go 25% further.
4:44 PM · Sep 22, 2026 · 320K Views

76 Replies · 109 Reposts · 1.76K Likes

I made a whole cheat sheet on how to master Claude Opus 5.5. Save it, share it.

Here’s what Anthropic is claiming:

→ It performs at the level of Fable 5.1 on most work

→ It costs about 40% less to run than Opus 5

→ It’s more than 30% faster than Opus 5

→ It’s now the default model on every paid Claude plan

→ Your usage limits go further, and you get a free limit reset

If those claims hold, the model you’ve been saving for “important” work stops being the obvious pick.

You could run most of your day on Opus 5.5 and keep Fable for the few jobs that need it.

But I don’t trust launch-day claims, and you shouldn’t either.

Every lab says its new model is the best.

Benchmarks get picked, demos get cherry-picked, and nobody posts the four attempts that broke.

Even Anthropic admits that at this level, benchmark scores are a less reliable guide to what you’ll feel in real work.

So I did what we always do here. I tested it in public.

I ran Opus 5.5 and Fable 5.1 side by side on the kind of work you do every week: writing, research, building a small tool, and catching a mistake before it goes out to your audience.

I test every major AI release on real work, three times a week. Subscribe so you don't miss the next one.


By the end of this issue, you’ll know:

→ How to get Opus 5.5 today, on any plan or platform

→ What it costs, and how to claim your free usage reset before it expires

→ Everything that changed from Opus 5

→ What people built with it in the first 24 hours

→ Which model won each of my head-to-head tests, and when Fable is still worth it

Plus, a gift at the end: 20 copy-paste prompts built around what Opus 5.5 does best.

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