GPT-5.3 Codex

GPT-5.3 Codex is a reasoning model from OpenAI. 19 benchmarks count toward its score, in 6 categories.

availableShows if the model has enough results for an index.
IndexOverall score out of 100.64.8 ±5.2
CoverageShare of the index weight with results.85%
SpeedOutput tokens per second.80/s
Input / 1MUS dollars per 1M input tokens.$1.75
Output / 1MUS dollars per 1M output tokens.$14
ContextMaximum tokens in one request.400K
EloLMArena rating and rank.N/A

The index is a score out of 100. The ± range shows how much it can change.

CapabilitiesScore per category, out of 100.

Out of 100
AgenticMulti-step tasks with tools.
60.7
CodingCode writing and repair.
64.1
ReasoningLogic problems and puzzles.
69.8
MultimodalTasks with images and text.
63.0
KnowledgeFacts and expert knowledge.
68.8
MultilingualTasks in many languages.
N/A
InstructionTasks with strict rules in the prompt.
65.6
MathMath problems.
N/A

Results

19 counted
BenchmarkThe test name.CategoryThe capability that the test measures.ResultThe score from the publisher.IndexThis result as a score out of 100.RunThe settings of the run.DateDate of the result.Published byThe source of the result.
Artificial Analysis GPQA DiamondKnowledge91.5%62.3Artificial Analysis
LiveCodeBenchCoding87.3%63.71 Sept 2026Vals AI
τ²-Bench Tool-Agent-User EvaluationAgentic86.0%60.5Victor Barres et al.
Software Engineering Benchmark VerifiedCoding85.0%65.7Carlos E. Jimenez et al.
Artificial Analysis Long Context ReasoningReasoning83.3%65.9Artificial Analysis
Artificial Analysis MMMU-ProMultimodal78.5%63.0Artificial Analysis
SWE-benchCoding78.0%60.11 Sept 2026Vals AI
Artificial Analysis IFBenchInstruction75.4%65.6Artificial Analysis
SWE-Bench verifiedCoding74.8%57.5high effortEpoch AI
OSWorld-VerifiedAgentic64.7%53.9Tianbao Xie et al.
Terminal-Bench 2.0Agentic64.0%68.44 Jun 2026Vals AI
Vibe Code Bench v1.1Coding61.8%67.9OpenHands21 Sept 2026Vals AI
SWE-RebenchCoding58.2%Nebius
Gert Labs Composite Game BenchmarkAgentic57.5%63.5Gert Labs
SWE-bench ProCoding56.8%58.9Xiang Deng et al.
IOICoding53.8%69.121 Sept 2026Vals AI
Artificial Analysis Omniscience AccuracyKnowledge52.9%79.3Artificial Analysis
IOI v1Coding43.8%64.99 Aug 2026Vals AI
Artificial Analysis Humanity's Last ExamKnowledge42.5%70.6Artificial Analysis
JobBenchAgentic33.7%57.3Yuetai Li et al.
Artificial Analysis Intelligence IndexKnowledge32.5%63.0Artificial Analysis
Critical Physics TasksReasoning16.9%73.8Artificial Analysis

19 benchmarks count, from 21 of 22 results. A grey row does not count. Too few models took that benchmark.

Sources

BenchLM benchmark aggregationUsed with attribution; per-benchmark results credited to their original authorsOpenRouter, collected directlyNo licence statedVals AI, collected directlyNo licence stated. Read from the public leaderboard and credited to Vals AIEpoch AI, collected directlyCC BY — free to use and redistribute with attribution

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