Claude Fable 5.1 wins on coding (100 vs 96) and writing quality. Kimi K3 wins on price ($3 vs $10/1M input). For most workflows, Claude Fable 5.1 is the stronger default — new frontier leader — better than fable 5 on every published benchmark, and cheaper to run.
The shortest way to see the safest default, the lower-cost option, and the specialist pick before you read deeper.
Claude Fable 5.1 is the safest overall answer here when you want the strongest default instead of the lowest list price.
Mistral: Mistral Nemo is the lower-cost option to start with when you still need useful output at scale.
Kimi K3 is the better pick when response speed matters more than maximum reasoning depth.
Claude Fable 5.1 leads on coding with a score of 100 vs 96 for Kimi K3.
Kimi K3 is cheaper at $3/1M input tokens vs $10/1M for Claude Fable 5.1.
Claude Fable 5.1 is the stronger default for coding tasks.
Choose Claude Fable 5.1 for frontier agentic coding, long-horizon autonomous work, and agentic scientific research. Its coding and research scores are what carry the recommendation here.
Switch to Kimi K3 when your work is mostly frontier-level reasoning and agentic coding; on that narrower brief it is the better tool.
Kimi K3 is the more cost-efficient option at $3/1M input — Claude Fable 5.1 costs 3x more per input token, so the gap is worth taking seriously wherever token volume rather than peak quality drives the bill.
Switch the scoring lens to see whether the top answer changes when you care more about cost, speed, or long-document work.
Anthropic / Premium / Sep 2, 2026
New frontier leader — better than Fable 5 on every published benchmark, and cheaper to run.
Ranks models by the broadest mix of coding, writing, research, and long-context usefulness.
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 fastest way to see where the recommendation shifts when your priority changes.
New frontier leader — better than Fable 5 on every published benchmark, and cheaper to run.
Closest Chinese challenger to the frontier — #4 overall on intelligence.
Every figure below is the provider's list price or a published capability score — the same numbers the recommendation on this page is built from.
| Model | Input | Output | Est. month | Context | Speed | Coding | Writing | Research |
|---|---|---|---|---|---|---|---|---|
| Claude Fable 5.1Anthropic | $5.00/1M | $25.00/1M | $100 | 1M tokens | Deliberate | 100 | 98 | 100 |
| Kimi K3Moonshot | $3.00/1M | $15.00/1M | $60 | 1M tokens | Deliberate | 96 | 90 | 93 |
Capability scores are out of 100 and reflect our own weighting of published benchmarks and production signals — see how we evaluate models. “Est. month” assumes 10M input and 2M output tokens at list price, with no batch or caching discounts applied, so treat it as a ceiling.
What each one is genuinely good at, where it falls down, and the situations we would steer you away from it — not just the headline score.
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.
Released September 1, 2026 alongside Claude Mythos 5.1, the first update to the Mythos-class line since Fable 5 on June 9. API ID claude-fable-5-1; generally available on the Claude API, Amazon Bedrock, Google Cloud, and Microsoft Foundry. Published launch numbers (Fable 5.1 / Fable 5 / Opus 5 / GPT-5.6 Sol): Terminal-Bench-Science 0.1 52.6 / 24.7 / 29.0 / 22.4; Terminal-Bench 4.0 55.8 / 42.0 / 52.3 / 37.3; CursorBench 3.2.0 73.4 / 70.5 / 70.0 / 67.2; AutomationBench 31.4 / 17.1 / 26.9 / 19.6; OSWorld 2.0 strict 41.7 / 36.1 / 39.6; Humanity's Last Exam (no tools) 60.9 / 57.8 / 56.6; GDPval-AA v2 1853 / 1723 / 1824 / 1711. GDPval-AA v2 is rescaled from the v1 numbers quoted on the Fable 5 page and is not directly comparable to them.
Moonshot's 2.8-trillion-parameter multimodal reasoning flagship with always-on thinking — the largest open-weight model ever released and the closest Chinese challenger to the Western frontier.
You need fast responses or predictable output costs — always-on thinking burns tokens.
The first Chinese model to genuinely crowd the Western frontier — #4 on aggregate intelligence ahead of Opus 4.8. The always-on thinking makes it slow and output-heavy, so cost per task runs above the sticker price. A serious Opus-class alternative if latency isn't critical.
Released July 16, 2026; open weights July 26. Cache-hit input $0.30/1M. Subscriptions: Adagio (free) to Vivace $199/mo; full 1M context only on Allegro ($99) and up. New signups paused July 19 near GPU capacity, reopening in batches.
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Claude Fable 5.1 wins on more of the categories we score — coding, research, long context — so it is the better default of the two. Kimi K3 is the better pick when your work is mostly frontier-level reasoning and agentic coding. Neither is universally "better": Claude Fable 5.1 is aimed at frontier agentic coding and long-horizon autonomous work, Kimi K3 at frontier-level reasoning and agentic coding.
Kimi K3 is cheaper at $3/1M input and $15/1M output. Claude Fable 5.1 costs $10/1M input and $50/1M output.
Both Claude Fable 5.1 and Kimi K3 have the same 1M context window.
Claude Fable 5.1 is better for coding with a score of 100 vs Kimi K3's 96 (out of 100). Claude Fable 5.1 is the overall coding leader in this directory at 100/100.
Both Claude Fable 5.1 and Kimi K3 have similar speed profiles — rated deliberate. Neither will be the bottleneck if latency is your deciding factor.
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. That is the main case for looking at Kimi K3 instead.
Most expensive Chinese-lab model ever ($3/$15) with always-on thinking driving high output-token burn and slow responses. 2.8T size makes self-hosting impractical despite open weights; consumer signups were paused July 19 over GPU capacity. Avoid it if you need fast responses or predictable output costs — always-on thinking burns tokens. Against Claude Fable 5.1 specifically, the gap shows up most on coding (100 vs 96).
Take a moderate workload of 10M input and 2M output tokens a month. Claude Fable 5.1 runs $200.00 (at $10/1M in and $50/1M out); Kimi K3 runs $60.00 (at $3/1M in and $15/1M out). That is a $140.00/month difference — Kimi K3 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 Fable 5.1 for frontier agentic coding and long-horizon autonomous work, with Kimi K3 handling frontier-level reasoning and agentic coding. Routing high-volume, low-stakes calls to Kimi K3 at $3/1M and reserving Claude Fable 5.1 for the hard cases is usually the cheapest arrangement that does not cost you quality.