Atlas

Models

← All models

GPT-5.1-Codex mini

OpenAI · 2025-11-13

GPT-5.1 Codex Mini is the smaller, more cost-efficient member of OpenAI's GPT-5.1 Codex API line. OpenAI released it for agentic coding workloads on November 13, 2025 alongside GPT-5.1 Codex, with a 400,000-token context window and configurable reasoning effort.

Benchmark scores

BenchmarkScore
AA-LCR62.7
AA-Omniscience Index-16.5
AIME 202591.7
Arena Code WebDev — Brand & Marketing1252
Arena Code WebDev — Consumer Product1241
Arena Code WebDev — Content Creation Tools1204
Arena Code WebDev — Data & Analytics1216
Arena Code WebDev — Gaming1249
Arena Code WebDev — HTML1254
Arena Code WebDev — Reference-Based Design1233
Arena Code WebDev — Simulations1228
Artificial Analysis Intelligence Index30.6
Artificial Analysis Omniscience Accuracy22.7
Artificial Analysis Omniscience Hallucination Rate50.8
BuseyBench SVG1.7
Capability145.1
CritPt0.0
Design Arena Overall Code Categories1123
Global MMLU Lite85.0
GPQA Diamond81.3
Humanity's Last Exam (Text-Only)16.9
IFBench (Artificial Analysis)67.9
LiveCodeBench (Artificial Analysis)83.6
LMArena Code Arena WebDev1247
MMLU Pro82.0
MMMU Pro69.0
Ruby LLM Benchmarks — Program Fixer66.7
Ruby LLM Program Fixer — Calendar86.7
Ruby LLM Program Fixer — Parking Garage32.8
Ruby LLM Program Fixer — School Library70.1
Loading Atlas data…