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OpenAI GPT-5.1-Codex

  • OpenAI
  • Released November 13, 2025
  • No public weights listed
  • 400K context

As of October 20, 2026, OpenAI GPT-5.1-Codex ranks #79 of 213 models overall with 23.7 on the Artificial Analysis Intelligence Index. Its strongest category is knowledge, where it ranks #49 of 147. OpenAI GPT-5.1-Codex costs $1.25 per million input tokens and $10.00 per million output tokens. It was released on November 13, 2025.

Its output price ranks 282 of 349 priced models, counting from the cheapest.

  • Coding index 50.5 Partial, 2 benchmarks
  • Cost per solved task $0.892 One SWE-bench Verified task, solved
  • Output, per million tokens $10.00 282 of 349 from the cheapest
  • Input, per million tokens $1.25 OpenRouter list price
  • Context window 400K Tokens per request

About and specs

GPT-5.1-Codex is a specialized version of GPT-5.1 optimized for software engineering and coding workflows. It is designed for both interactive development sessions and long, independent execution of complex engineering tasks....

API model id openai/gpt-5.1-codex
  • Tool callingListed
  • Structured outputsListed
  • JSON modeListed
  • Reasoning modeListed
  • Web searchNot listed
Takes in
Text, Images
Gives back
Text
Context window
400K tokens
Max output
128K tokens
Knowledge cutoff
September 30, 2024, per OpenAI model documentation
Cached input $/Mtok
$0.13
Cache write $/Mtok
No cache write price listed
Reasoning $/Mtok
Not priced apart
Web search, per request
$0.01
Tokenizer
GPT
Requests moderated
No
Withdrawn on
No date announced
Parameters
Not published
Downloads, all time
No public weights
Training compute
No estimate published
Output speed
Not measured
Time to first token
Not measured
Speed on OpenRouter
Not measured
First token on OpenRouter
Not measured

Benchmarks: 26 of 190 measured

The tick on a coding bar is the median of every model measured on it. Outside coding, the place is this model's rank on that board. A board that never ran the model says so.

Coding index

50.5
  • Aider polyglot Not measured
  • SWE-bench Verified 66.0% 66 of 100
  • LiveBench coding Not measured
  • LMArena WebDev Elo, scaled from 1200 to 1900 1337 Elo 20 of 100

The index averages only the coding benchmarks that have a result; the others are skipped, never filled in. How it is weighted

Other public boards

All rankings

Coding7 of 34 boards

1 more coding boards

Not measured on SWE-bench Lite, SWE-bench (full test set), SWE-bench Multimodal, SWE-bench Multilingual, AA Coding Index, SWE-bench Verified (Vals AI), Terminal-Bench 4 (Vals AI), Code migration (Vals AI), ProgramBench (Vals AI), IOI (Vals AI), Terminal-Bench 2.1 (Vals AI), SWE-bench Multimodal (Vals AI), Vibe Code Bench 1-100 (Vals AI), SkillsBench (Vals AI), CyberBench (Vals AI), SciCode, DeepSWE, FrontierCode, FrontierSWE, GSO-Bench, WeirdML, MirrorCode, Cybench, LMArena Text: coding, LMArena Text: software and IT, LMArena WebDev: React, LMArena WebDev: from an image

Intelligence1 of 2 boards

Not measured on Epoch Capabilities Index

Agentic work4 of 39 boards

Not measured on AA Agentic Index, Design Arena: agents building Android apps, Design Arena: agents building Godot games, Design Arena: agents building games, Design Arena: HTML slides, Design Arena: PowerPoint slides, Design Arena: spreadsheets, LiveBench research, LiveBench browser, LiveBench long agentic, SREBench (Vals AI), Finance Agent (Vals AI), Tax Agent Bench (Vals AI), Legal Research Bench (Vals AI), Harvey's Legal Agent Benchmark (Vals AI), Excel Modeling Benchmark (Vals AI), BioMysteryBench (Vals AI), Terminal-Bench-Science (Vals AI), Vals Science Index, Time Horizon Index (Vals AI), CUA-bench (Vals AI), Robo-bench (Vals AI), APEX-Agents, METR time horizons, Remote Labor Index, GDPval, OSWorld 2.0, BALROG, DeepResearch Bench, PostTrainBench, TheAgentCompany, OSWorld, SpireClimb, Vending-Bench 2, LMArena Search

Reasoning2 of 21 boards

Not measured on GPQA Diamond, LiveBench reasoning, MysteryMechanism (Vals AI), MMMU Pro (Vals AI), GPQA Diamond (Epoch AI run), ARC-AGI, ARC-AGI-2, Humanity's Last Exam, SimpleBench, Chess puzzles, Mystery game puzzles, EBR-bench, VPCT, BIG-Bench Hard, LMArena Text: hard prompts, LMArena Text: expert, LMArena Text: hard prompts in English, LMArena Vision: diagrams, LMArena Vision: homework

Math2 of 13 boards

Not measured on AIME, MATH 500 (Vals AI), MGSM (Vals AI), OTIS Mock AIME, FrontierMath, tiers 1 to 3, FrontierMath, tier 4, ProofBench, MATH level 5, GSM8K, LMArena Text: math, LMArena Text: mathematical work

Knowledge1 of 17 boards

Not measured on MMLU Pro, LegalBench (Vals AI), CaseLaw (Vals AI), CorpFin (Vals AI), TaxEval (Vals AI), MortgageTax (Vals AI), MedQA (Vals AI), MedCode (Vals AI), SimpleQA Verified, MMLU, GeoBench, AI2 Reasoning Challenge, LMArena Text: science, LMArena Text: medicine and healthcare, LMArena Text: legal and government, LMArena Text: business and finance

Web design5 of 9 boards

Not measured on Design Arena: 3D, Design Arena: SVG, Design Arena: ASCII art, LiveBench design

General2 of 46 boards

Not measured on Vals Index, LiveBench data analysis, Public Benefits Bench (Vals AI), SAGE (Vals AI), MedScribe (Vals AI), Vals Multimodal Index, DTBench, LMCA, Fiction.LiveBench, Creative writing (Lech Mazur), CL-bench, Surface Evolver Bench, Furniture assembly, ExploitBench, HellaSwag, WinoGrande, PIQA, CL-bench Life, LMArena Text, LMArena Text: instruction following, LMArena Text: creative writing, LMArena Vision, LMArena Text: English, LMArena Text: non-English, LMArena Text: Chinese, LMArena Text: German, LMArena Text: Japanese, LMArena Text: Korean, LMArena Text: French, LMArena Text: Spanish, LMArena Text: Russian, LMArena Text: Polish, LMArena Text: multi-turn, LMArena Text: longer queries, LMArena Text: writing and language, LMArena Text: entertainment and media, LMArena Vision: English, LMArena Vision: Chinese, LMArena Vision: reading text, LMArena Vision: humor, LMArena Vision: captioning, LMArena Vision: recognizing things, LMArena Vision: creative writing, LMArena Document

Image generation0 of 5 boards

Not measured on Design Arena: images, Design Arena: graphic design, Design Arena: logos, LMArena Text to Image, LMArena Image Edit

Public boards shown as published (Vals AI, Artificial Analysis, Design Arena) and kept out of the coding index. Each links to its source on the benchmark page.

All 190 benchmarks as a table
Benchmark results for OpenAI GPT-5.1-Codex
BenchmarkResultIndex weight
Aider polyglotCoding Not measured 35%
SWE-bench VerifiedCoding 66.0% 30%
SWE-bench LiteCoding Not measured Not in index
SWE-bench (full test set)Coding Not measured Not in index
SWE-bench MultimodalCoding Not measured Not in index
SWE-bench MultilingualCoding Not measured Not in index
LiveBench codingCoding Not measured 20%
LMArena WebDevCoding 1337 15%
Vals IndexGeneral Not measured Not in index
GPQA DiamondReasoning Not measured Not in index
AIMEMath Not measured Not in index
MMLU ProKnowledge Not measured Not in index
AA Intelligence IndexIntelligence 23.7 Not in index
AA Coding IndexCoding Not measured Not in index
AA Agentic IndexAgentic work Not measured Not in index
Design Arena: websitesWeb design 1162 Not in index
Design Arena: UI componentsWeb design 1238 Not in index
Design Arena: game devWeb design 1138 Not in index
Design Arena: data vizWeb design 1213 Not in index
Design Arena: 3DWeb design Not measured Not in index
Design Arena: all code categoriesWeb design 1153 Not in index
Design Arena: SVGWeb design Not measured Not in index
Design Arena: ASCII artWeb design Not measured Not in index
Design Arena: agents building web appsAgentic work 1018 Not in index
Design Arena: agents building full-stack appsAgentic work 1086 Not in index
Design Arena: agents building mobile appsAgentic work 1191 Not in index
Design Arena: agents building Android appsAgentic work Not measured Not in index
Design Arena: agents building Godot gamesAgentic work Not measured Not in index
Design Arena: agents building gamesAgentic work Not measured Not in index
Design Arena: HTML slidesAgentic work Not measured Not in index
Design Arena: PowerPoint slidesAgentic work Not measured Not in index
Design Arena: spreadsheetsAgentic work Not measured Not in index
Design Arena: imagesImage generation Not measured Not in index
Design Arena: graphic designImage generation Not measured Not in index
Design Arena: logosImage generation Not measured Not in index
LiveBench reasoningReasoning Not measured Not in index
LiveBench data analysisGeneral Not measured Not in index
LiveBench researchAgentic work Not measured Not in index
LiveBench browserAgentic work Not measured Not in index
LiveBench long agenticAgentic work Not measured Not in index
LiveBench designWeb design Not measured Not in index
LiveCodeBench (Vals AI)Coding 85.5% Not in index
SWE-bench Verified (Vals AI)Coding Not measured Not in index
Terminal-Bench 4 (Vals AI)Coding Not measured Not in index
Vibe Code Bench (Vals AI)Coding 13.1% Not in index
Code migration (Vals AI)Coding Not measured Not in index
ProgramBench (Vals AI)Coding Not measured Not in index
SREBench (Vals AI)Agentic work Not measured Not in index
IOI (Vals AI)Coding Not measured Not in index
Terminal-Bench 2.1 (Vals AI)Coding Not measured Not in index
SWE-bench Multimodal (Vals AI)Coding Not measured Not in index
Vibe Code Bench 1-100 (Vals AI)Coding Not measured Not in index
SkillsBench (Vals AI)Coding Not measured Not in index
CyberBench (Vals AI)Coding Not measured Not in index
Finance Agent (Vals AI)Agentic work Not measured Not in index
Tax Agent Bench (Vals AI)Agentic work Not measured Not in index
Legal Research Bench (Vals AI)Agentic work Not measured Not in index
Harvey's Legal Agent Benchmark (Vals AI)Agentic work Not measured Not in index
Excel Modeling Benchmark (Vals AI)Agentic work Not measured Not in index
BioMysteryBench (Vals AI)Agentic work Not measured Not in index
Terminal-Bench-Science (Vals AI)Agentic work Not measured Not in index
Vals Science IndexAgentic work Not measured Not in index
Time Horizon Index (Vals AI)Agentic work Not measured Not in index
CUA-bench (Vals AI)Agentic work Not measured Not in index
Robo-bench (Vals AI)Agentic work Not measured Not in index
Public Benefits Bench (Vals AI)General Not measured Not in index
MysteryMechanism (Vals AI)Reasoning Not measured Not in index
MMMU Pro (Vals AI)Reasoning Not measured Not in index
MATH 500 (Vals AI)Math Not measured Not in index
MGSM (Vals AI)Math Not measured Not in index
SAGE (Vals AI)General Not measured Not in index
LegalBench (Vals AI)Knowledge Not measured Not in index
CaseLaw (Vals AI)Knowledge Not measured Not in index
CorpFin (Vals AI)Knowledge Not measured Not in index
TaxEval (Vals AI)Knowledge Not measured Not in index
MortgageTax (Vals AI)Knowledge Not measured Not in index
MedQA (Vals AI)Knowledge Not measured Not in index
MedCode (Vals AI)Knowledge Not measured Not in index
MedScribe (Vals AI)General Not measured Not in index
Vals Multimodal IndexGeneral Not measured Not in index
AA Math IndexMath 95.7 Not in index
GPQA Diamond (Artificial Analysis run)Reasoning 86.0% Not in index
Humanity's Last Exam (Artificial Analysis run)Reasoning 25.7% Not in index
MMLU Pro (Artificial Analysis run)Knowledge 86.0% Not in index
LiveCodeBench (Artificial Analysis run)Coding 84.9% Not in index
SciCodeCoding Not measured Not in index
Terminal-Bench Hard (Artificial Analysis run)Coding 34.8% Not in index
IFBenchGeneral 70.0% Not in index
Long context reasoning (AA-LCR)General 69.3% Not in index
τ²-Bench TelecomAgentic work 83.0% Not in index
AIME 2025 (Artificial Analysis run)Math 95.7% Not in index
Terminal-BenchCoding 57.8% Not in index
DeepSWECoding Not measured Not in index
FrontierCodeCoding Not measured Not in index
FrontierSWECoding Not measured Not in index
GSO-BenchCoding Not measured Not in index
WeirdMLCoding Not measured Not in index
MirrorCodeCoding Not measured Not in index
APEX-AgentsAgentic work Not measured Not in index
METR time horizonsAgentic work Not measured Not in index
Remote Labor IndexAgentic work Not measured Not in index
GDPvalAgentic work Not measured Not in index
OSWorld 2.0Agentic work Not measured Not in index
BALROGAgentic work Not measured Not in index
DeepResearch BenchAgentic work Not measured Not in index
PostTrainBenchAgentic work Not measured Not in index
GPQA Diamond (Epoch AI run)Reasoning Not measured Not in index
ARC-AGIReasoning Not measured Not in index
ARC-AGI-2Reasoning Not measured Not in index
Humanity's Last ExamReasoning Not measured Not in index
SimpleBenchReasoning Not measured Not in index
Chess puzzlesReasoning Not measured Not in index
Mystery game puzzlesReasoning Not measured Not in index
EBR-benchReasoning Not measured Not in index
OTIS Mock AIMEMath Not measured Not in index
FrontierMath, tiers 1 to 3Math Not measured Not in index
FrontierMath, tier 4Math Not measured Not in index
ProofBenchMath Not measured Not in index
MATH level 5Math Not measured Not in index
GSM8KMath Not measured Not in index
SimpleQA VerifiedKnowledge Not measured Not in index
MMLUKnowledge Not measured Not in index
GeoBenchKnowledge Not measured Not in index
DTBenchGeneral Not measured Not in index
LMCAGeneral Not measured Not in index
Fiction.LiveBenchGeneral Not measured Not in index
Creative writing (Lech Mazur)General Not measured Not in index
CL-benchGeneral Not measured Not in index
Surface Evolver BenchGeneral Not measured Not in index
Furniture assemblyGeneral Not measured Not in index
ExploitBenchGeneral Not measured Not in index
CybenchCoding Not measured Not in index
TheAgentCompanyAgentic work Not measured Not in index
OSWorldAgentic work Not measured Not in index
SpireClimbAgentic work Not measured Not in index
VPCTReasoning Not measured Not in index
BIG-Bench HardReasoning Not measured Not in index
AI2 Reasoning ChallengeKnowledge Not measured Not in index
HellaSwagGeneral Not measured Not in index
WinoGrandeGeneral Not measured Not in index
PIQAGeneral Not measured Not in index
CL-bench LifeGeneral Not measured Not in index
ALE-BenchCoding 1244.9 Not in index
Vending-Bench 2Agentic work Not measured Not in index
Epoch Capabilities IndexIntelligence Not measured Not in index
LMArena TextGeneral Not measured Not in index
LMArena Text: codingCoding Not measured Not in index
LMArena Text: hard promptsReasoning Not measured Not in index
LMArena Text: mathMath Not measured Not in index
LMArena Text: instruction followingGeneral Not measured Not in index
LMArena Text: creative writingGeneral Not measured Not in index
LMArena VisionGeneral Not measured Not in index
LMArena Text: EnglishGeneral Not measured Not in index
LMArena Text: non-EnglishGeneral Not measured Not in index
LMArena Text: ChineseGeneral Not measured Not in index
LMArena Text: GermanGeneral Not measured Not in index
LMArena Text: JapaneseGeneral Not measured Not in index
LMArena Text: KoreanGeneral Not measured Not in index
LMArena Text: FrenchGeneral Not measured Not in index
LMArena Text: SpanishGeneral Not measured Not in index
LMArena Text: RussianGeneral Not measured Not in index
LMArena Text: PolishGeneral Not measured Not in index
LMArena Text: multi-turnGeneral Not measured Not in index
LMArena Text: longer queriesGeneral Not measured Not in index
LMArena Text: expertReasoning Not measured Not in index
LMArena Text: hard prompts in EnglishReasoning Not measured Not in index
LMArena Text: software and ITCoding Not measured Not in index
LMArena Text: mathematical workMath Not measured Not in index
LMArena Text: scienceKnowledge Not measured Not in index
LMArena Text: medicine and healthcareKnowledge Not measured Not in index
LMArena Text: legal and governmentKnowledge Not measured Not in index
LMArena Text: business and financeKnowledge Not measured Not in index
LMArena Text: writing and languageGeneral Not measured Not in index
LMArena Text: entertainment and mediaGeneral Not measured Not in index
LMArena WebDev: ReactCoding Not measured Not in index
LMArena WebDev: HTMLCoding 1346 Not in index
LMArena WebDev: from an imageCoding Not measured Not in index
LMArena Vision: EnglishGeneral Not measured Not in index
LMArena Vision: ChineseGeneral Not measured Not in index
LMArena Vision: reading textGeneral Not measured Not in index
LMArena Vision: diagramsReasoning Not measured Not in index
LMArena Vision: homeworkReasoning Not measured Not in index
LMArena Vision: humorGeneral Not measured Not in index
LMArena Vision: captioningGeneral Not measured Not in index
LMArena Vision: recognizing thingsGeneral Not measured Not in index
LMArena Vision: creative writingGeneral Not measured Not in index
LMArena SearchAgentic work Not measured Not in index
LMArena DocumentGeneral Not measured Not in index
LMArena Text to ImageImage generation Not measured Not in index
LMArena Image EditImage generation Not measured Not in index

What it costs

A list price says what a token costs. The cost per solved task says what a working answer costs, which is the number that decides.

Output price against the market

GPT-5.1-Codex pricing
$0.0112Dashed line: median $1.80, log scale$600.00
$10.00 per million output tokens is cheaper than 14% of the 344 paid models in the catalog.

Cost per solved task

How it is computed
$0.5889one attempt, swebench.com 66.0%tasks solved $0.892per solved task

Nearly as good as GPT-5.1-Codex, for less

What the boards say about its runs

Beside a result, many boards publish what the run cost, how long it took, the tokens it spent or the votes behind a rating. Each figure as its board printed it, one board per row.

What each board publishes about the runs behind OpenAI: GPT-5.1-Codex's results
BoardResultWhat the run costAlso published
SWE-bench Verified 66.0% $0.5889 per attempt Nothing else
Vibe Code Bench (Vals AI) 13.1% $3.80 per test Duration, as printed 50m 26s
ALE-Bench 1244.9 $0.5121 per problem Tokens per problem 54,011
LMArena WebDev 1337 Elo Not published Votes 5,007 · Interval (±) ±11.6
Design Arena: websites 1162 Elo Not published Battles 1,453
Design Arena: UI components 1238 Elo Not published Battles 115
Design Arena: game dev 1138 Elo Not published Battles 182
Design Arena: data viz 1213 Elo Not published Battles 118
Design Arena: all code categories 1153 Elo Not published Battles 2,005
Design Arena: agents building web apps 1018 Elo Not published Battles 525
LiveCodeBench (Vals AI) 85.5% Not published Latency, as printed 3m 54s
LMArena WebDev: HTML 1346 Elo Not published Votes 4,991 · Interval (±) ±13.0

On these lists

Compare with models of a similar score

All 135 comparisons for GPT-5.1-Codex