The best AI for developers isn't the one with the highest MMLU score — it's the one that catches the bug you missed at 11pm, writes tests that actually test something, and doesn't hallucinate library APIs. These picks are ranked on SWE-bench performance, context window for large codebases, and the practical experience of working with them daily.
Last verified:
/Rankings refresh daily when model data changes
Rankings refresh dailyScored on 6 criteriaNo paid rankings
Best pick right now
AnthropicPremium
Claude Opus 5.5
Anthropic's new coding default — top SWE-bench Pro score at a lower price than Opus 5.
Your tasks are well-scoped and latency-sensitive — Sonnet 5.5 is half the price and Anthropic says it is the fastest Sonnet yet.
Strengths
SWE-bench Pro 89.9% in Anthropic's launch table, ahead of Claude Fable 5.1 (81.2%) and Opus 5 (79.2%)
Cheaper than the model it replaces: $4/$20 per 1M against Opus 5's $5/$25, and cache reads at $0.20/1M
1M context and 128K output at standard rates, with effort levels up to max
Weaknesses
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
Ranked alternatives
Strong backups depending on your budget, workload, and preferred tradeoffs.
OpenAIPremium
GPT-6 Astra
OpenAI's September 3, 2026 frontier release — the first GPT-6 model and OpenAI's answer to Claude Fable 5.1 two days earlier. State of the art on computer use (OSWorld 2.0 72.6% in ~47% less time than GPT-5.6 Sol), agentic coding (Terminal-Bench 4.0 57.9%), and frontier math (FrontierMath Tier 4 97.6%). $10/$50 per 1M tokens, 1.05M context, 128K output, knowledge cutoff April 30, 2026.
Verdict
OpenAI's frontier answer to Fable 5.1 — computer-use and agentic-coding leader at $10/$50.
Quality score
98%
Pricing
$10.00/1M in
$50.00/1M out
Speed
Deliberate
2/5 speed
Context
1.1M tokens
Released September 3, 2026. API ID gpt-6-astra; rolling out over the coming days to ChatGPT Plus, Pro, Business and Enterprise (usage inside existing allowances; GPT-6 Astra Pro for Pro/Business/Enterprise; Enterprise off by default), the OpenAI API, Microsoft Azure and Amazon Bedrock. Standard API pricing $10/$50 per 1M tokens; Fast mode is up to 2x speed at 2x price; cache reads and writes have separate rates. Model docs list 1,050,000 context, 128,000 max output, knowledge cutoff April 30, 2026, reasoning efforts up to 'max'. Published launch numbers (Astra / GPT-5.6 Sol / Fable 5.1 / Opus 5): OSWorld 2.0 72.6 / 65.7 / — / 70.2; Terminal-Bench 4.0 57.9 / 37.3 / 55.8 / 52.3; Terminal-Bench Science 0.1 64.6 / 22.4 / 52.6 / 30.0; FrontierMath Tier 4 v2 97.6 / 83.0 / 87.8 / 73.2; GPQA Diamond 96.0 / 94.6 / 93.7 / 93.7; Humanity's Last Exam w/ tools 57.2 / — / 65.0 / 63.6; AutomationBench 41.4 / 18.1 / 31.4 / 26.9; DeepSWE v1.1 74.1 / 72.7 / 67.4 / 73.7; ARC-AGI-2 95.0 / 92.5 / 90.0 / 90.4; ARC-AGI-3 99.9 (OpenAI responses-API harness; ARC Prize's stateless runs score far lower) / 7.8 / — / 30.2; ExploitBench 100.0 / 78.5 / — / 70; SRE-Bench 88.0 / 55.9; Artificial Analysis Intelligence Index v4.1.1 61.2 / 60.9 / 65.7 / 63.1. Meets the Critical threshold for cybersecurity under OpenAI's Preparedness Framework; advanced cyber workflows gated behind OpenAI Daybreak. All figures from OpenAI's launch post and model docs, verified September 4, 2026.
Computer use leaderFrontierAgenticReasoningLong contextPremiumNew
Best for
Computer and browser use, long-horizon agentic coding, and frontier math and science work
Anthropic's September 1, 2026 frontier release for coding, agents, and scientific work. On SWE-bench Pro the cheaper Claude Opus 5.5 now scores higher (89.9% vs 81.2% in Anthropic's table). 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.
Verdict
Anthropic's highest-ceiling model — strongest on open-ended research; Opus 5.5 now leads coding.
Quality score
98%
Pricing
$10.00/1M in
$50.00/1M out
Speed
Deliberate
2/5 speed
Context
1M 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.
The unrestricted twin of Claude Fable 5.1 — the same model with safeguards lifted in high-risk areas, released September 1, 2026 to vetted cybersecurity and life-sciences organisations under Anthropic's trusted-access programme. Scores 60.9% on Terminal-Bench 4.0, the highest agentic-coding result Anthropic has published.
Verdict
Fable 5.1 with the safeguards lifted — partner-only, 60.9% Terminal-Bench 4.0.
Quality score
97%
Pricing
$10.00/1M in
$50.00/1M out
Speed
Deliberate
2/5 speed
Context
1M tokens
Released September 1, 2026 alongside Claude Fable 5.1, continuing the Mythos-class line that began with Project Glasswing's April 2026 private preview. Access is limited to vetted US cybersecurity and life-sciences professionals. Same underlying model, pricing, context window, and cache-read discount as Fable 5.1; the only published difference is the safeguard level and the resulting Terminal-Bench 4.0 score (60.9% vs 55.8%).
Anthropic's most agentic Sonnet yet — a fast 1M-context workhorse that narrows the gap to Opus-class quality at $3/$15, and the new default model on claude.ai.
Verdict
Agentic Sonnet, now replaced by the faster, cheaper Sonnet 5.5.
Quality score
95%
Pricing
$2.00/1M in
$10.00/1M out
Speed
Fast
4/5 speed
Context
1M tokens
Released June 30, 2026. Default model for Free and Pro claude.ai plans. Promo pricing $2/$10 per 1M through Aug 31, 2026, then $3/$15. 128K max output, Jan 2026 knowledge cutoff.
AgenticCodingWriting1M contextBest value
Best for
High-volume agentic workloads and production apps at mid-tier pricing
Our pick for developers. It scores 100/100 on the coding axis we weight this page by, and nothing else in this shortlist matches it on output quality.
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.
Input
$4.00/1M
Output
$20.00/1M
Context
1M tokens
Speed
Deliberate
What people actually use it for
Repository-scale changes and PR work — Anthropic reports 89.9% on SWE-bench Pro, up from 79.2% for Opus 5
Long unattended agent runs where per-task token spend matters as much as the per-token price
Reports, analysis and briefs that need to state findings and next steps plainly
Where it wins
SWE-bench Pro 89.9% in Anthropic's launch table, ahead of Claude Fable 5.1 (81.2%) and Opus 5 (79.2%)
Cheaper than the model it replaces: $4/$20 per 1M against Opus 5's $5/$25, and cache reads at $0.20/1M
1M context and 128K output at standard rates, with effort levels up to max
Where it falls down
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
Skip 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.
Our verdict
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.
Here for latency: it answers fastest of anything listed for developers, at 99/100 on coding.
OpenAI's September 3, 2026 frontier release — the first GPT-6 model and OpenAI's answer to Claude Fable 5.1 two days earlier. State of the art on computer use (OSWorld 2.0 72.6% in ~47% less time than GPT-5.6 Sol), agentic coding (Terminal-Bench 4.0 57.9%), and frontier math (FrontierMath Tier 4 97.6%). $10/$50 per 1M tokens, 1.05M context, 128K output, knowledge cutoff April 30, 2026.
Input
$10.00/1M
Output
$50.00/1M
Context
1.1M tokens
Speed
Deliberate
What people actually use it for
Computer-use agents that fill forms, update CRMs, run QA in a browser — 72.6% on OSWorld 2.0 at ~40 minutes per task vs Sol's 75
Agentic coding in Codex with cross-context notes — 57.9% Terminal-Bench 4.0, ahead of Claude Fable 5.1 (55.8%)
Frontier math and science — 97.6% FrontierMath Tier 4 and 64.6% Terminal-Bench Science, both well clear of every rival OpenAI tested
Where it wins
OSWorld 2.0 72.6% vs 65.7% for GPT-5.6 Sol, in roughly 47% less time per task — the new computer-use ceiling
Terminal-Bench 4.0 57.9% — ahead of Claude Fable 5.1 (55.8%), Opus 5 (52.3%) and GPT-5.6 Sol (37.3%)
FrontierMath Tier 4 (v2) 97.6% vs Fable 5.1's 87.8%; Terminal-Bench Science 64.6% vs 52.6%; GPQA Diamond 96.0%
1.05M context with 96.3% on OpenAI MRCR 8-needle at 512K–1M (Sol: 73.8%) and 128K max output
OpenAI's lowest misaligned-outcome rates to date: 2.4% on its computer-use safety benchmark vs 22.0% for Sol, 0% scope-creep on impossible cyber tasks vs 48%
Where it falls down
$10/$50 per 1M — two and a half times GPT-5.6 Sol's $4/$20 promotional rate, five times GPT-6.1 Sol's $2/$10, and the same premium as Claude Fable 5.1; Fast mode doubles it again
Trails Claude Fable 5.1 on Humanity's Last Exam with tools (57.2% vs 65.0%) and on the Artificial Analysis Intelligence Index (61.2 vs 65.7)
OpenAI published no SWE-bench Verified or SWE-bench Pro figure at launch, so it does not appear on our SWE-bench leaderboard
Rolling out over days, not instantly: Enterprise access is off by default, advanced cyber tasks are refused outside OpenAI Daybreak, and the safety layer can pause or stop legitimate agent runs
OpenAI's own system card finds its written reasoning harder to monitor than Sol's
Skip it if
You are cost-sensitive or latency-bound — GPT-5.6 Sol is a fifth of the price — or you need it today in an Enterprise workspace, where it is off by default, or for offensive-security work, which it refuses outside OpenAI Daybreak.
Our verdict
The new computer-use and agentic-coding ceiling, and OpenAI's first model priced like a Mythos-class Claude. Astra beats Claude Fable 5.1 on Terminal-Bench 4.0 (57.9% vs 55.8%), Terminal-Bench Science (64.6% vs 52.6%) and FrontierMath Tier 4 (97.6% vs 87.8%), and it is the only model with a credible OSWorld 2.0 result above 70%. It loses to Fable 5.1 on Humanity's Last Exam and on Artificial Analysis's index, costs five times GPT-5.6 Sol, and ships without a SWE-bench number. If your work is computer use, browser agents or math, it is the pick; for everyday coding at scale, GPT-6.1 Sol at $2/$10 is the value default — OpenAI says it comes close to Astra at a fifth of the price.
Full pricing, benchmark table and release notes on the GPT-6 Astra page.
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FAQ
What is the best AI for developers?
For developers, Claude Opus 5.5 (Anthropic) is our pick. Anthropic's new coding default — top SWE-bench Pro score at a lower price than Opus 5. It costs $4/1M input and $20/1M output tokens, with a 1M-token context window — enough headroom for all but the largest developers jobs. GPT-6 Astra is the closest alternative if it doesn't fit your setup.
Why Claude Opus 5.5 for developers?
Because the work it is built for overlaps closely with developers: repository-scale changes and PR work — Anthropic reports 89.9% on SWE-bench Pro, up from 79.2% for Opus 5 and long unattended agent runs where per-task token spend matters as much as the per-token price. 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.
What does it cost to use Claude Opus 5.5 for developers?
On a moderate month — 10M input and 2M output tokens — Claude Opus 5.5 runs about $80.00 at list price, with no batch or caching discounts applied, so treat that as a ceiling. Claude Sonnet 5 is the cheaper route at roughly $40.00 for the same volume, if developers is high-volume enough for price to lead the decision.
When is Claude Opus 5.5 the wrong choice for developers?
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. 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. None of that rules it out for developers on its own — but if one of those limits maps onto how you actually work, take the alternative on this page seriously rather than defaulting to the top pick.
Is there a cheaper AI that still handles developers?
Claude Sonnet 5 at $2/1M input is the budget option here. Agentic Sonnet, now replaced by the faster, cheaper Sonnet 5.5. Expect a quality step down on the hardest cases — the usual pattern is to route routine developers volume to Claude Sonnet 5 and keep Claude Opus 5.5 for the work where a wrong answer is expensive.
Which of these is fastest?
Claude Sonnet 5, rated fast against Claude Opus 5.5's deliberate. Speed matters most for interactive and high-volume work; if your developers runs in the background, the slower and more capable model is usually the better trade.