Claude Fable 5 is the strongest alternative to Claude Fable 5.1 — it matches it on coding (100/100) at $10/1M input (Claude Fable 5.1 costs $10/1M). Claude Opus 4.8 is the budget swap: $5/1M input is 50% cheaper. Kimi K3 is the top open-weight option if you want a model you can self-host.
The shortest way to see the safest default, the lower-cost option, and the specialist pick before you read deeper.
Claude Fable 5 is the safest overall answer here when you want the strongest default instead of the lowest list price.
Grok 4.5 is the lower-cost option to start with when you still need useful output at scale.
Claude Fable 5.1 is the better pick when response speed matters more than maximum reasoning depth.
Claude Fable 5 matches Claude Fable 5.1 on coding (100/100) at $10/1M input tokens.
Claude Opus 4.8 cuts input cost by 50% ($5 vs $10/1M) while scoring 100/100 on coding.
Kimi K3 is open-weight — self-host it or run it via low-cost API providers at $3/1M input.
Choose Claude Fable 5 when you want the closest overall replacement — it targets the hardest coding tasks, autonomous multi-step agents, and frontier-grade reasoning.
Choose Claude Opus 4.8 when token volume matters more than peak quality — it is 50% cheaper on input.
Staying with Anthropic? Claude Fable 5 is the strongest in-house switch at $10/1M input.
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 1, 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.
Superseded by Fable 5.1 — still 80.3% SWE-Bench Pro, but 5.1 is better and cheaper to run.
Best value premium coder — frontier-grade at half of Fable 5's price.
Closest Chinese challenger to the frontier — #4 overall on intelligence.
Fable 5.1 with the safeguards lifted — partner-only, 60.9% Terminal-Bench 4.0.
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 5Anthropic | $10.00/1M | $50.00/1M | $200 | 1M tokens | Deliberate | 100 | 98 | 100 |
| Claude Fable 5.1Anthropic | $10.00/1M | $50.00/1M | $200 | 1M tokens | Deliberate | 100 | 98 | 100 |
| Claude Opus 4.8Anthropic | $5.00/1M | $25.00/1M | $100 | 1M tokens | Deliberate | 100 | 96 | 98 |
| 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 new Mythos-class flagship and the most capable coding model anyone can use — 80.3% SWE-Bench Pro, an 11-point jump over Opus 4.8. 1M context, 128K output, native parallel subagents. Released June 9, 2026.
You are starting new work — Claude Fable 5.1 supersedes it at the same base price with 75% cheaper cache reads. Also skip it if you are latency- or cost-sensitive.
Superseded by Claude Fable 5.1 on September 1, 2026, which beats it on every benchmark Anthropic published and costs less to run thanks to a 75% cache-read cut. Fable 5 remains a frontier-class model — 80.3% SWE-Bench Pro, an 11-point leap over Opus 4.8 — and stays available at the same $10/$50, but there is no reason to start new work on it.
Launched June 9, 2026 as the public, Mythos-class release. Available on the Claude API, Microsoft Foundry, and Google Vertex AI. Free for all users until June 22, 2026. Same underlying model as Claude Mythos 5, with safeguards that block specific high-risk cyber responses. Superseded by Claude Fable 5.1 on September 1, 2026 — same $10/$50 base pricing, cache reads cut from $1.00 to $0.25 per 1M tokens.
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.
Anthropic's newest Opus flagship — 69.2% SWE-Bench Pro, 88.6% SWE-Bench Verified, 1890 Arena Elo (121 pts ahead of GPT-5.5), and native parallel subagents. Same $5/$25 price as Opus 4.7.
You need the highest possible coding ceiling (Fable 5 / Mythos 5), low-latency responses, or a workflow locked to OpenAI tooling.
The best value at the premium tier now that Claude Fable 5 leads on raw capability. 69.2% SWE-Bench Pro, 1890 Elo, and built-in parallel subagents at $5/$25 — half the price of Fable 5. The smart default for serious coding when you don't need the absolute frontier.
Launched May 27, 2026. Available on Claude API, AWS Bedrock, Google Vertex AI, Microsoft Foundry, and GitHub Copilot. Fast mode available at $10/$50 per 1M tokens.
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 is the strongest overall alternative. It scores 100/100 on coding (Claude Fable 5.1: 100/100) and costs $10/1M input vs $10/1M. Superseded by Fable 5.1 — still 80.3% SWE-Bench Pro, but 5.1 is better and cheaper to run.
Claude Opus 4.8 at $5/1M input — 50% cheaper than Claude Fable 5.1's $10/1M. It scores 100/100 on coding, so expect a quality step down on the hardest tasks.
Yes — Kimi K3 is the strongest open-weight replacement for Claude Fable 5.1, scoring 96/100 on coding against Claude Fable 5.1's 100/100. You can self-host it or run it through hosted APIs at $3/1M input (Claude Fable 5.1 costs $10/1M), with no per-seat subscription. Self-hosting trades the licence saving for infrastructure you have to run, so it pays off at sustained volume rather than for occasional use.
Claude Fable 5 — same provider, same API surface, $10/1M input vs $10/1M. Superseded by Fable 5.1 — still 80.3% SWE-Bench Pro, but 5.1 is better and cheaper to run.
The new frontier leader, and the rare upgrade that costs less than the model it replaces.