Claude Fable 5.1 wins on coding (100 vs 93) and writing quality. DeepSeek V4-Pro wins on price ($0.435 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.
Last verified Sep 1, 2026/Model data modified Sep 1, 2026
Rankings refresh dailyScored on 6 criteriaNo paid rankings
AnthropicPremium
Input cost
$10.00/1M
Context
1M tokens
Speed
Deliberate
Clear recommendation block
The shortest way to see the safest default, the lower-cost option, and the specialist pick before you read deeper.
DeepSeek V4-Pro is the better pick when response speed matters more than maximum reasoning depth.
DeepSeekBudget
Best for
Frontier-level coding and reasoning on a budget
Price
$0.43/1M
Context
1M tokens
Why this page recommends it
Claude Fable 5.1 leads on coding with a score of 100 vs 93 for DeepSeek V4-Pro.
DeepSeek V4-Pro is cheaper at $0.435/1M input tokens vs $10/1M for Claude Fable 5.1.
Claude Fable 5.1 is the stronger default for coding tasks.
Decision notes
Go with Claude Fable 5.1 if you want one model to handle coding and research — it targets frontier agentic coding, long-horizon autonomous work, and agentic scientific research.
Switch to DeepSeek V4-Pro when your work is mostly frontier-level coding and reasoning on a budget; on that narrower brief it is the better tool.
DeepSeek V4-Pro is the more cost-efficient option at $0.435/1M input — Claude Fable 5.1 costs 23x more per input token, so the gap is worth taking seriously wherever token volume rather than peak quality drives the bill.
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#1Claude Fable 5.191 pts
#2DeepSeek V4-Pro83 pts
Quality first
Claude Fable 5.1
Anthropic / Premium / Sep 1, 2026
91
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.
Recommended comparisons
The fastest way to see where the recommendation shifts when your priority changes.
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.
The case for each model
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.
Input
$10.00/1M
Output
$50.00/1M
Context
1M tokens
Speed
Deliberate
What people actually use it for
Agentic scientific research — 52.6% on Terminal-Bench-Science 0.1, more than double Fable 5's 24.7%
Long-running autonomous coding agents that plan, run, and debug across a whole repository
Cache-heavy agent loops where the 75% cache-read cut ($1.00 → $0.25 per 1M) is the real saving
Where it wins
52.6% Terminal-Bench-Science 0.1 — 2.1x Fable 5 (24.7%), well clear of Opus 5 (29.0%) and GPT-5.6 Sol (22.4%)
55.8% Terminal-Bench 4.0 agentic coding, ahead of Opus 5 (52.3%) and Fable 5 (42.0%)
Cache reads cut 75% to $0.25/1M — ~25% cheaper for typical use, ~45% for heavily agentic work
Independent Vals AI evaluation ranks it #1 of 51 on the Vals Index, #1 on LiveCodeBench (90.5%) and MMLU Pro (92.4%)
1M-token context and 128K max output at standard rates, with adaptive thinking always enabled
Where it falls down
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
Deliberate, high-latency profile — the wrong choice for interactive, latency-bound apps
Skip 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.
Our verdict
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.
DeepSeek's 1.6T-parameter (49B active) MoE flagship with hybrid sparse attention — near-frontier coding and reasoning at roughly a tenth of closed-rival pricing, MIT-licensed open weights.
Input
$0.43/1M
Output
$0.87/1M
Context
1M tokens
Speed
Balanced
What people actually use it for
Repository-level coding — 80.6% SWE-bench Verified (self-reported), the top open-weights score at release
Self-hosted frontier capability under an MIT license
Where it wins
80.6% SWE-bench Verified (self-reported) — reported as tied with Gemini 3.1 Pro
93.5% LiveCodeBench and Codeforces 3206 — elite competitive-coding results
1M context with 384K max output at $0.87/1M output — an order of magnitude cheaper than closed frontier models
Where it falls down
Independent harnesses report much lower agentic scores than the self-reported numbers; trails GPT-5.6 and Opus-class on hard agentic evals
Peak-hour surge pricing doubles rates, a price increase is announced, and it's text-only (no vision)
Skip it if
You need vision input, verified agentic performance, or predictable pricing (surge pricing and an announced increase loom).
Our verdict
The open-weights frontier flagship of 2026. Self-reported numbers flatter it and independent agentic scores land lower, but even discounted it's the most capability per dollar in the directory's upper tier — with MIT-licensed weights.
Open-weight preview April 24; GA ~July 20, 2026. Off-peak pricing verified on api-docs.deepseek.com; Beijing-business-hours surge doubles it. Legacy deepseek-chat/reasoner endpoints retired July 24, 2026.
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FAQ
Is Claude Fable 5.1 better than DeepSeek V4-Pro?
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. DeepSeek V4-Pro is the better pick when your work is mostly frontier-level coding and reasoning on a budget. Neither is universally "better": Claude Fable 5.1 is aimed at frontier agentic coding and long-horizon autonomous work, DeepSeek V4-Pro at frontier-level coding and reasoning on a budget.
Which is cheaper — Claude Fable 5.1 or DeepSeek V4-Pro?
DeepSeek V4-Pro is cheaper at $0.435/1M input and $0.87/1M output. Claude Fable 5.1 costs $10/1M input and $50/1M output.
Which has a larger context window — Claude Fable 5.1 or DeepSeek V4-Pro?
Both Claude Fable 5.1 and DeepSeek V4-Pro have the same 1M context window.
Is Claude Fable 5.1 or DeepSeek V4-Pro better for coding?
Claude Fable 5.1 is better for coding with a score of 100 vs DeepSeek V4-Pro's 93 (out of 100). Claude Fable 5.1 is the overall coding leader in this directory at 100/100.
Which is faster — Claude Fable 5.1 or DeepSeek V4-Pro?
DeepSeek V4-Pro is faster with a balanced speed rating (score: 3) vs Claude Fable 5.1's deliberate rating (score: 2). Speed matters most for interactive and high-throughput work; for batch jobs the Claude Fable 5.1 latency penalty is usually invisible.
What are the downsides of Claude Fable 5.1?
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 DeepSeek V4-Pro instead.
What are the downsides of DeepSeek V4-Pro?
Independent harnesses report much lower agentic scores than the self-reported numbers; trails GPT-5.6 and Opus-class on hard agentic evals. Peak-hour surge pricing doubles rates, a price increase is announced, and it's text-only (no vision). Avoid it if you need vision input, verified agentic performance, or predictable pricing (surge pricing and an announced increase loom). Against Claude Fable 5.1 specifically, the gap shows up most on coding (100 vs 93).
What does a month of real work cost on Claude Fable 5.1 vs DeepSeek V4-Pro?
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); DeepSeek V4-Pro runs $6.09 (at $0.435/1M in and $0.87/1M out). That is a $193.91/month difference — DeepSeek V4-Pro 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.
Can I use Claude Fable 5.1 and DeepSeek V4-Pro together?
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 DeepSeek V4-Pro handling frontier-level coding and reasoning on a budget. Routing high-volume, low-stakes calls to DeepSeek V4-Pro at $0.435/1M and reserving Claude Fable 5.1 for the hard cases is usually the cheapest arrangement that does not cost you quality.