Claude Opus 5.5 wins on coding (100 vs 99) and price ($4 vs $10/1M input). For most workflows, Claude Opus 5.5 is the stronger default — anthropic's new coding default — top swe-bench pro score at a lower price than opus 5.
The safest Claude Opus 5.5 vs Claude Fable 5.1 default, the cheaper option worth trying first, and the specialist pick — before you read the detail below.
Claude Opus 5.5 is the strongest answer here for Claude Opus 5.5 vs Claude Fable 5.1 — pick it when quality of output matters more than the $4.00/1M/1M input you pay for it.
Claude Sonnet 5.5 handles the same job for about 50% less per token. Start here and only move up if the output is not good enough.
Claude Fable 5.1 is the fastest of these for Claude Opus 5.5 vs Claude Fable 5.1 — worth it when latency is what the reader notices, not the last few points of reasoning depth.
Claude Opus 5.5 leads on coding with a score of 100 vs 99 for Claude Fable 5.1.
Claude Opus 5.5 is cheaper at $4/1M input tokens vs $10/1M for Claude Fable 5.1.
Claude Opus 5.5 is the stronger default for coding tasks.
Choose Claude Opus 5.5 for agentic coding, long-running agents and knowledge work where Opus 5 was the bar. Its coding and research scores are what carry the recommendation here.
Claude Fable 5.1 earns its place when your work is mostly frontier agentic coding and long-horizon autonomous work, even though it loses the overall count here.
Both models serve different primary workflows — Claude Opus 5.5 for agentic coding and long-running agents and knowledge work where Opus 5 was the bar, Claude Fable 5.1 for frontier agentic coding and long-horizon autonomous work — so running each where it has a clear edge often beats forcing one to do both.
Switch the scoring lens to see whether the Claude Opus 5.5 vs Claude Fable 5.1 answer changes when cost, speed, or long-document depth leads the decision.
Anthropic / Premium / Oct 10, 2026
Anthropic's new coding default — top SWE-bench Pro score at a lower price than Opus 5.
Ranks models by the broadest mix of coding, writing, research, and long-context usefulness.
Your tasks are well-scoped and latency-sensitive — Sonnet 5.5 is half the price and Anthropic says it is the fastest Sonnet yet.
Where the Claude Opus 5.5 vs Claude Fable 5.1 recommendation shifts once you weigh price or latency differently.
Anthropic's new coding default — top SWE-bench Pro score at a lower price than Opus 5.
Anthropic's highest-ceiling model — strongest on open-ended research; Opus 5.5 now leads coding.
List prices and published scores — the numbers this page's pick is built from.
| Model | Input | Output | Est. month | Context | Speed | Coding | Writing | Research |
|---|---|---|---|---|---|---|---|---|
| Claude Opus 5.5Anthropic | $4.00/1M | $20.00/1M | $80 | 1M tokens | Deliberate | 100 | 97 | 99 |
| Claude Fable 5.1Anthropic | $10.00/1M | $50.00/1M | $200 | 1M tokens | Deliberate | 99 | 98 | 100 |
Scores out of 100 — how we evaluate models. “Est. month” is 10M in / 2M out at list price: a ceiling, no discounts.
Why each one is on the shortlist for Claude Opus 5.5 vs Claude Fable 5.1, what it is genuinely good at, and where we would steer you away from it.
Ranked first here for Claude Opus 5.5 vs Claude Fable 5.1: 100/100 on coding, with the widest margin of anything in this line-up.
Anthropic's September 22, 2026 Opus — a step up from Opus 5 on agentic coding, long-running agent work and vision, at a lower $4/$20 list price and with fewer tokens spent per finished task.
Your tasks are well-scoped and latency-sensitive — Sonnet 5.5 is half the price and Anthropic says it is the fastest Sonnet yet.
The new premium coding default from Anthropic. Opus 5.5 posts the highest SWE-bench Pro figure in any launch table we track and costs less than Opus 5 did. Fable 5.1 still makes sense for the hardest open-ended research at $10/$50; for almost everything else Opus 5.5 is the better buy, and Sonnet 5.5 at half the price is close behind on well-scoped work.
Full pricing, benchmark table and release notes on the Claude Opus 5.5 page.
Here for latency: it answers fastest of anything listed for Claude Opus 5.5 vs Claude Fable 5.1, at 99/100 on coding.
Anthropic's September 1, 2026 frontier release and the new capability ceiling for coding, agents, and scientific work. Base pricing is unchanged at $10/$50, but cache reads dropped 75% to $0.25/1M — roughly 25% cheaper on typical workloads and up to 45% cheaper on agentic ones. 1M context, 128K output, adaptive thinking always on.
You need low latency, or your workload is uncached and cost-sensitive — Claude Opus 5 is half the base price and within a few points on agentic coding.
The new frontier leader, and the rare upgrade that costs less than the model it replaces. Base $10/$50 pricing did not move, but a 75% cut to cache reads makes typical workloads ~25% cheaper than Fable 5 and heavily agentic ones ~45% cheaper — while more than doubling Fable 5 on agentic science and beating Opus 5 on agentic coding. If you were already on Fable 5, switching is a straight win. If you were on Opus 5 for the price, it still costs 2x on uncached tokens.
Full pricing, benchmark table and release notes on the Claude Fable 5.1 page.
UseRightAI recommendations are based on practical decision factors people actually feel in day-to-day use.
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Claude Opus 5.5 wins on more of the categories we score — coding, research, reasoning — so it is the better default of the two. Claude Fable 5.1 is the better pick when your work is mostly frontier agentic coding and long-horizon autonomous work. Neither is universally "better": Claude Opus 5.5 is aimed at agentic coding and long-running agents and knowledge work where Opus 5 was the bar, Claude Fable 5.1 at frontier agentic coding and long-horizon autonomous work.
Claude Opus 5.5 is cheaper at $4/1M input and $20/1M output. Claude Fable 5.1 costs $10/1M input and $50/1M output.
Both Claude Opus 5.5 and Claude Fable 5.1 have the same 1M context window.
Claude Opus 5.5 is better for coding with a score of 100 vs Claude Fable 5.1's 99 (out of 100). Claude Opus 5.5 is the overall coding leader in this directory at 100/100.
Both Claude Opus 5.5 and Claude Fable 5.1 have similar speed profiles — rated deliberate. Neither will be the bottleneck if latency is your deciding factor.
Not ahead everywhere: Anthropic's own table has Opus 5 higher on Toolathlon Verified (80.6% vs 77.8%). Fast mode doubles the price to $8/$40. Terminal-Bench 4.0 differs by effort setting (66.4% at xhigh, 64.8% at max), so single-digit gaps against rivals are directional. Avoid it if your tasks are well-scoped and latency-sensitive — Sonnet 5.5 is half the price and Anthropic says it is the fastest Sonnet yet. That is the main case for looking at Claude Fable 5.1 instead.
Base rates are still $10/$50 per 1M — double Claude Opus 5 for anything that is not cache-heavy. Anthropic published no SWE-bench Verified or SWE-bench Pro figure for 5.1 at launch. On Claude Pro it only runs on pay-as-you-go credits; Max includes it up to 50% of weekly limits. Avoid it if you need low latency, or your workload is uncached and cost-sensitive — Claude Opus 5 is half the base price and within a few points on agentic coding. Against Claude Opus 5.5 specifically, the gap shows up most on coding (100 vs 99).
Take a moderate workload of 10M input and 2M output tokens a month. Claude Opus 5.5 runs $80.00 (at $4/1M in and $20/1M out); Claude Fable 5.1 runs $200.00 (at $10/1M in and $50/1M out). That is a $120.00/month difference — Claude Opus 5.5 is the cheaper of the two at this volume, and the gap scales linearly as you send more. Output tokens dominate the bill on both, so prompt length matters far less than response length.
Yes, and for most teams that beats picking one. A common split is Claude Opus 5.5 for agentic coding and long-running agents and knowledge work where Opus 5 was the bar, with Claude Fable 5.1 handling frontier agentic coding and long-horizon autonomous work. Since Claude Opus 5.5 is both the stronger and the cheaper option here, a split mainly makes sense if Claude Fable 5.1 covers a capability you specifically need.