OpenAI · model passport
OpenAI: GPT-5.2-Codex
gpt-5-2-codex- Cloud only
- Proprietary licence
- 400,000 context
- Released 2026-10-13(first seen on LMArena)
- Best percentile
- 96.0IFBench (Artificial Analysis)
- Cohort standing
- 63.1median 60.6
What the data says
Benchmarked on 4 of 27 tracked axes. Every figure below is the model's own published result on that board.
Strongest axes
- 96 pct — IFBench (Artificial Analysis) (77.6%)
- 90.4 pct — LiveBench (74.0%)
Uneven: 74.4 percentile points between its best and worst axis — 96 pct on IFBench (Artificial Analysis) versus 21.6 pct on WebDev Arena.
- IFBench (Artificial Analysis)96 pct77.6%Verify →
- LiveBench90.4 pct74.0%Verify →
- Terminal-Bench84.1 pct66.5%Verify →
- WebDev Arena21.6 pct1,339Verify →
- OverallNot benchmarked
- Vision ArenaNot benchmarked
- Factuality ArenaNot benchmarked
- Search ArenaNot benchmarked
- Document ArenaNot benchmarked
- Agent ArenaNot benchmarked
- GPQA DiamondNot benchmarked
- AIME (math)Not benchmarked
- FrontierMathNot benchmarked
- SimpleQA VerifiedNot benchmarked
- ARC-AGI-2Not benchmarked
- Humanity's Last ExamNot benchmarked
- SimpleBenchNot benchmarked
- BFCL v4 (function calling)Not benchmarked
- SWE-bench Verified (live board)Not benchmarked
- Terminal-Bench 4.0Not benchmarked
- MMLU-Pro (Artificial Analysis)Not benchmarked
- LiveCodeBench (Artificial Analysis)Not benchmarked
- HHEM Hallucination (Vectara)Not benchmarked
- SWE-bench VerifiedNot benchmarked
- CodingNot benchmarked
- Instruction followingNot benchmarked
- Hard promptsNot benchmarked
Percentiles are the model's standing within each board's own population. Axes marked "not benchmarked" have no published result for this model — that is an absence of data, not a low score.
How to run it
Use it hosted
openai/gpt-5.2-codexAPI parameters this endpoint supports
Example request
curl https://openrouter.ai/api/v1/chat/completions \
-H "Authorization: Bearer $OPENROUTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model":"openai/gpt-5.2-codex","messages":[{"role":"user","content":"Hello"}]}'Identifiers, limits and prices are synced from the upstream source shown above. Any field we haven't synced is left out entirely rather than guessed.
GPT-5.2-Codex stands at 63.1 (raw mean 73) — measured on 4 of 27 axes.
GPT-5.2-Codex stands at 63.1 versus a cohort median of 60.6 across 168 models released within 180 days — above the peer median.
GPT-5.2-Codex scores in the 96th percentile on IFBench (Artificial Analysis).
GPT-5.2-Codex scores at percentile 90.4 on LiveBench.
GPT-5.2-Codex ranks between #37 and #370 across 4 built-in weightings — best under "Agentic", worst under "All-rounder".
Every claim is a computed fact from the current board data, phrased by a low-temperature model call and rejected by a validation gate if any number is not in the source row. How the leaderboards work →