Model profile
GPT-5.3 Codex
Evidence coverage
21 of 321 tracked benchmarks are published. 8 are verified and 13 provisional. 6 of 8 categories are measured.
- Published / tracked
- 21 / 321
- Verified
- 8
- Provisional
- 13
- Categories with evidence
- 6 / 8
Evidence by category
- Agentic5 benchmarksMixed evidence
- Coding5 benchmarksMixed evidence
- Reasoning2 benchmarksReported
- Knowledge6 benchmarksReported
- Math0 benchmarksNot measured
- Multilingual0 benchmarksNot measured
- Multimodal2 benchmarksReported
- Inst. Following1 benchmarkReported
GPT-5.3 Codex ranks #26 out of 200 models on the public leaderboard with an overall score of 66.69/100. It also ranks #23 out of 99 on the verified leaderboard. This places it in the mid-tier of AI models, with strengths in specific benchmark categories.
GPT-5.3 Codex is a proprietary model with a 400K token context window. It uses explicit chain-of-thought reasoning, which typically improves performance on math and complex reasoning tasks at the cost of higher latency and token usage.
GPT-5.3 Codex sits inside the GPT-5.3 Codex family alongside GPT-5.3-Codex-Spark. This profile currently has 21 of 321 tracked benchmarks. BenchLM only exposes non-generated benchmark rows publicly, so missing categories stay blank until a sourced evaluation is available.
Its strongest category is Agentic (#10), while its weakest is Coding (#14). This performance profile makes it particularly useful for coding agents, browser research, and computer-use workflows.
Peer position
Exact provisional scores and ranks for the closest listed peers. A score can appear before a model clears the evidence threshold for a rank, so equal scores can have different rank states.
Range 66.27–67.22
- Qwen3.7 PlusAlibabaCompare#2167.22Qwen3.7 Plus is #21 with a score of 67.22.
- GPT-5.6 LunaOpenAICompare#2267.17GPT-5.6 Luna is #22 with a score of 67.17.
- GPT-5.2 ProOpenAICompare#2367.01GPT-5.2 Pro is #23 with a score of 67.01.
- GLM-5-TurboZ.AICompare#2466.89GLM-5-Turbo is #24 with a score of 66.89.
- GPT-5.4 nanoOpenAICompare#2566.79GPT-5.4 nano is #25 with a score of 66.79.
- GPT-5.3 CodexCurrent modelOpenAI#2666.69GPT-5.3 Codex is #26 with a score of 66.69.
- Claude Opus 4.7 (Adaptive)AnthropicCompare#2766.27Claude Opus 4.7 (Adaptive) is #27 with a score of 66.27.
Category percentile
More
Relative position among models eligible for each sourced category. A higher percentile means a stronger position within that category's ranked cohort; 100 is highest.
- Agentic92%Eligible cohort rank #10 of 119Category score 61.2
- Coding89%Eligible cohort rank #14 of 122Category score 64.2
Category evidence
Scores and ranks appear only where this model has published benchmark evidence. Categories without displayable source records remain not measured.
| Category | Score | Rank | Percentile | Weight | Benchmarks | Evidence |
|---|---|---|---|---|---|---|
| AgenticRank #10 of 119Percentile 92ndWeight 22%5 benchmarksMixed sources | 61.2 | #10 of 119 | 92nd | 22% | 5 benchmarks | Mixed sources |
| CodingRank #14 of 122Percentile 89thWeight 20%5 benchmarksMixed sources | 64.2 | #14 of 122 | 89th | 20% | 5 benchmarks | Mixed sources |
| ReasoningRank Not rankedWeight 17%2 benchmarksReported | 92.4 | Not ranked | Not available | 17% | 2 benchmarks | Reported |
| KnowledgeRank Not rankedWeight 12%6 benchmarksReported | 70.7 | Not ranked | Not available | 12% | 6 benchmarks | Reported |
| MathWeight 5%0 benchmarksNot measured | Not measured | Not ranked | Not available | 5% | 0 benchmarks | Not measured |
| MultilingualWeight 7%0 benchmarksNot measured | Not measured | Not ranked | Not available | 7% | 0 benchmarks | Not measured |
| MultimodalRank Not rankedWeight 12%2 benchmarksReported | 91.0 | Not ranked | Not available | 12% | 2 benchmarks | Reported |
| Inst. FollowingRank Not rankedWeight 5%1 benchmarkReported | 83.3 | Not ranked | Not available | 5% | 1 benchmark | Reported |
Chatbot Arena performance
Scroll horizontally to inspect confidence intervals and vote counts.
| View | Elo | Confidence interval | Votes |
|---|---|---|---|
| Text Overall | 1416 | Not available | Not available |
Benchmark Details
Rows below have a displayable published verification record. Each source link and provenance note remains in the page HTML while its category is closed. Source-unverified manual rows and generated rows stay hidden.
Agentic5 benchmarks
τ²-Bench Tool-Agent-User Evaluation
Gert Labs Composite Game Benchmark
Coding5 benchmarks
Software Engineering Benchmark Verified
Vibe Code Bench v1.1
Artificial Analysis SciCode
Reasoning2 benchmarks
Artificial Analysis Long Context Reasoning
Critical Physics Tasks
Knowledge6 benchmarks
Artificial Analysis GPQA Diamond
Artificial Analysis Humanity's Last Exam
Artificial Analysis Omniscience Index
Artificial Analysis Omniscience Accuracy
Artificial Analysis Omniscience Hallucination Rate
Multimodal2 benchmarks
Artificial Analysis MMMU-Pro
Design Arena Website Elo
Inst. Following1 benchmark
Artificial Analysis IFBench
Frequently Asked Questions
How does GPT-5.3 Codex perform overall in AI benchmarks?
GPT-5.3 Codex has 21 published benchmark scores on BenchLM, but it does not yet have enough non-generated coverage to receive a global overall rank.
Is GPT-5.3 Codex good for knowledge and understanding?
GPT-5.3 Codex has visible benchmark coverage in knowledge and understanding, but BenchLM does not currently assign it a global category rank there.
Is GPT-5.3 Codex good for coding and programming?
GPT-5.3 Codex ranks #14 out of 122 models in coding and programming benchmarks with an average score of 64.2. There are stronger options in this category.
Is GPT-5.3 Codex good for reasoning and logic?
GPT-5.3 Codex has visible benchmark coverage in reasoning and logic, but BenchLM does not currently assign it a global category rank there.
Is GPT-5.3 Codex good for agentic tool use and computer tasks?
GPT-5.3 Codex ranks #10 out of 119 models in agentic tool use and computer tasks benchmarks with an average score of 61.2. It is among the top performers in this category.
Is GPT-5.3 Codex good for multimodal and grounded tasks?
GPT-5.3 Codex has visible benchmark coverage in multimodal and grounded tasks, but BenchLM does not currently assign it a global category rank there.
Is GPT-5.3 Codex good for instruction following?
GPT-5.3 Codex has visible benchmark coverage in instruction following, but BenchLM does not currently assign it a global category rank there.
Which sibling models are related to GPT-5.3 Codex?
GPT-5.3 Codex belongs to the GPT-5.3 Codex family. Related variants on BenchLM include GPT-5.3-Codex-Spark.
Does GPT-5.3 Codex have full benchmark coverage on BenchLM?
Not yet. GPT-5.3 Codex currently has 21 published benchmark scores out of the 321 benchmarks BenchLM tracks. BenchLM only exposes non-generated public benchmark rows, so missing categories stay blank until a sourced evaluation is available.
What is the context window size of GPT-5.3 Codex?
GPT-5.3 Codex has a published context window of 400K, which determines how much text it can process in a single interaction.
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