OpenAI

GPT-5.2-Codex

GPT-5.2-Codex is a proprietary model from OpenAI, released Jan 14, 2026. Its best result is #9 of 143 on LiveCodeBench with 87.99%. It costs $1.75 per million input tokens and $14 per million output tokens, with a 400K-token context window.

Developer
OpenAI
Released
Jan 14, 2026
Context window
400K
Price in / out, per 1M tokens
$1.75 / $14
Weights
Proprietary
Inputs
Text, Images
Reasoning
Yes
Tool use
Yes

Benchmarks

BenchmarkScore barAccuracyRankCost / test
SWE-benchCoding72.40%52 / 85$0.31
Vibe Code BenchCoding37.91%68 / 115$4.15
LiveCodeBenchCoding87.99%9 / 143$1.75 / $14

Vals AI, as of Oct 24, 2026.

LMArena, by category

LeaderboardRatingRankVotes
WebDevLMArena1339123 / 1246.7K

LMArena, CC BY 4.0, as of Oct 22, 2026. Where a model is rated at several effort levels, its best is shown.

Compare GPT-5.2-Codex

OpenAI

The lab behind GPT and ChatGPT, which brought large language models to hundreds of millions of people. Founded 2015, based in San Francisco. openai.com

Questions

Who makes GPT-5.2-Codex?

GPT-5.2-Codex is made by OpenAI, founded 2015 and based in San Francisco.

How much does GPT-5.2-Codex cost?

$1.75 per million input tokens and $14 per million output tokens, at its provider’s list price.

What is GPT-5.2-Codex’s context window?

400K tokens (400,000).

Is GPT-5.2-Codex open source?

No. GPT-5.2-Codex is proprietary and served through its provider’s API.

Sources

Every number on this page comes from these sources; models without a published number show none. Download the data. Cite as “Nexus Explorer, nexus.inc/models”.