BenchLeader

GPT-5.2-Codex

Reasoning effort

GPT-5.2-Codex is an OpenAI proprietary reasoning model, released 18 Dec 2025. Its best configuration (xhigh reasoning effort) ranks #133 of 785 on the BenchLeader Index at 59.4 ±4.5, in the upper half. The ± is the point: 231 other configurations score within that range, so they and this one cannot be told apart on quality alone — price and speed are what separate them. It scores highest in instruction following (75) and lowest in reasoning (55). At $4.81 per million tokens blended it is among the most expensive ranked models. Output speed of 81 tokens per second puts it slower than most, with a first answer in 145.1 s. It has been measured at 3 reasoning-effort settings; this summary describes the best-scoring one, and the tabs above switch between them. Last measured 11 Dec 2025.stale: no new result in six months

Blended price
$4.81/M
$1.75 in · $14.00 out
Output speed
81 tok/s
measured by Artificial Analysis
First answer
145 s
first token 3.08 s
Context
400k
Full answer
151 s
median, reasoning included
Cost per run
–
Released
18 Dec 2025
How it scores by categoryDashed line = average model (50). One step of 15 = one standard deviation.
  1. Overall index59
  2. Reasoning55
  3. Agents & tools66
  4. Knowledge61
  5. Instruction following75
  6. Multimodal59
  7. Long context66
  8. Composite61

Versions

OpenAI has shipped 5 models under this name. Each is ranked on its own results; a newer version often has fewer results so far, which holds its index nearer the average until more arrive.

ModelReleasedIndexRank
GPT-5.3-Codexxhigh5 Feb 202663.8#60
GPT-5.2-Codexxhighthis page18 Dec 202559.4#133
GPT-5.1-Codexhigh12 Nov 202556.3#208
GPT-5-Codexhigh15 Sept 202557.5#177
GPT 5.5 Codex–––

Reasoning-effort configurations

The same model behaves differently depending on how much it is allowed to think. Each row is one setting, scored only on the benchmarks that were run at that setting. “Not stated” collects results from publishers that did not say which setting they used; for a reasoning model that is usually its thinking mode, but we do not assume it. Pick a setting here or at the top of the page to see its price, speed and category scores.

EffortIndexRankSpeedFirst answerChat reply costCategories
high––43 tok/s3.08 s$0.0049
xhighbest59.4#13381 tok/s145 s$0.0049Agents & tools 66 · Composite 61 · Instruction following 75 · Knowledge 61 · Long context 66 · Multimodal 59 · Reasoning 55
not stated57.3#18343 tok/s3.08 s$0.0049Agents & tools 68 · Coding 55

How its index has moved

8 Sept 2026 to 23 Oct 2026
485765
  • xhigh
  • not stated

The index is recomputed from scratch every day, so a line moves when a new benchmark result lands, when a publisher revises a score, or when the models it is normalised against change. Early movement usually means the score is still settling.

Benchmark results

See all LLM benchmarks. One column per reasoning effort. Rank is among every configuration of every model on that benchmark. Hover a score for the run it came from.

Reasoning

Benchmarkxhighnot statedSourceTrend
LiveBench 1.0 Reasoningnot in indexeffort not stated–77.7%#56LiveBench
GPQA Diamond (AA)not in index89.9%#67–Artificial Analysis
Humanity's Last Exam (AA)not in index35.7%#114–Artificial Analysis
CritPt8.7%#133–Artificial Analysis

Coding

Benchmarkhighnot statedSourceTrend
Arena WebDeveffort not stated–1339#112Arena (LMArena)
LiveBench 1.0 Codingnot in indexeffort not stated–83.6%#8LiveBench
LiveCodeBencheffort not stated–88.0%#9Vals AI
SWE-bench (Vals)not in index72.4%#53–Vals AI
SWE-Bench Proeffort not stated–41.0%#11Scale AI SEAL
SWE-bench Verified (bash only)effort not stated–72.8%#7SWE-bench
SWE-bench Verified (any scaffold)not in indexeffort not stated–72.8%#10SWE-bench
Vibe Code Bench v1.1not in index37.9%#68–Vals AI
SWE-Bench Pro (private)not in indexeffort not stated–41.0%#11Scale AI SEAL
ALE-Benchnot in indexeffort not stated–1299.9#34Epoch AI Benchmarking Hub

Agents & tools

Benchmarkxhighnot statedSourceTrend
Terminal-Bencheffort not stated–66.5%#8Terminal-Bench
LiveBench Agentic Codingnot in indexeffort not stated–49.4%#45LiveBench
Terminal-Bench Hard37.1%#69–Artificial Analysis
τ²-Bench Telecom (AA)not in index92.1%#53–Artificial Analysis

Maths

Benchmarknot statedSourceTrend
LiveBench Mathematicsnot in index88.8%#41LiveBench

Knowledge

Benchmarkxhighnot statedSourceTrend
LiveBench 1.0 Data Analysisnot in indexeffort not stated–78.2%#26LiveBench
AA-Omniscience-2.2#148–Artificial Analysis
AA-Omniscience: accuracynot in index41.1%#116–Artificial Analysis
AA-Omniscience: non-hallucinationnot in index26.6%#232–Artificial Analysis

Instruction following

Benchmarkxhighnot statedSourceTrend
LiveBench Languagenot in indexeffort not stated–73.7%#54LiveBench
LiveBench Instruction Followingnot in indexeffort not stated–66.5%#41LiveBench
IFBench77.6%#16–Artificial Analysis

Multimodal

BenchmarkxhighSourceTrend
MMMU-Pro76.3%#91Artificial Analysis

Long context

BenchmarkxhighSourceTrend
AA-LCR82.3%#41Artificial Analysis

Composite

Benchmarkxhighnot statedSourceTrend
LiveBench 1.0not in indexeffort not stated–74.0%#43LiveBench
AA Intelligence Index v4.3.228.5#134–Artificial Analysis

Where to run it

Every provider serving this model through OpenRouter, with throughput and first-token latency measured on live traffic over the last 30 minutes and each provider’s own price. Purple marks the best in each column.

ProviderSpeedFirst tokenInput $/MOutput $/MContextQuantisation
Azure46 tok/s1.71 s$1.75$14.00400k–

What a task costs

Estimates from list price, output speed and time to first answer for the best configuration. “With caching” assumes three-quarters of the input is served from the prompt cache at $0.175 per 1M. Reasoning tokens are not modelled.

WorkloadTokens in / outCostWith cachingTime
Chat reply400 / 300$0.0049$0.00442.5 min
Summarize a 30-page report12,000 / 600$0.029$0.0152.5 min
Code edit6,000 / 1,500$0.032$0.0242.7 min
Agentic coding session60,000 / 4,000$0.161$0.0903.2 min
Structured extraction2,000 / 200$0.0063$0.00392.5 min

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See also

Questions people ask

What are GPT-5.2-Codex's benchmark scores?
As of 24 Oct 2026, GPT-5.2-Codex (xhigh effort) scores 59.4 ±4.5 on the BenchLeader Index, strongest in instruction following (75) and weakest in reasoning (55). That rests on 7 independent benchmark results, and every score on this page links to its publisher.
How does GPT-5.2-Codex rank?
GPT-5.2-Codex (xhigh effort) is #133 of 785 ranked configurations on 24 Oct 2026. 231 other configurations score within its margin, so the exact position matters less than the band. The leader is Claude Opus 5.5 (max effort) at 72.6.
How much does GPT-5.2-Codex cost per 1M tokens?
As of 24 Oct 2026, GPT-5.2-Codex costs $1.75 per 1M input tokens and $14.00 per 1M output tokens, $4.81 blended (three input tokens per output token).
When was GPT-5.2-Codex released?
OpenAI released GPT-5.2-Codex on 18 Dec 2025. BenchLeader has results for it at 3 reasoning-effort settings.

Data as of 24 Oct 2026. Compare these configurations.

Cite as: BenchLeader, “GPT-5.2-Codex: benchmarks, pricing, speed and rank”, data as of 24 Oct 2026, https://www.benchleader.com/models/gpt-5-2-codex.