Glimmer Index
Plus $4/mo

GPT-5.1 Codex Max

OpenAI · Released Nov 13, 2025 · Closed weights

Coding-optimized GPT model for repository edits, reviews, and agentic software work

Strongest at
Math
Better than 5% of the past year's models · one benchmark so far
Price per 1M tokens
$1.25 / $10
input / output · OpenRouter
Context window
400K
tokens in · 128K out
Lab announcement ↗Open in the timeline

Capability profile

Where it lands among 91 models released in the past year. 50 is the average model.

This modelEvery model from the past year
Coding
No results yet
Writing
No results yet
Reading & documents
No results yet
Reasoning
No results yet
Math
37Better than 5% · 1 test
Science
No results yet
Visual reasoning
No results yet
Computer use
No results yet
Where these scores come from

Each capability combines the published benchmarks listed here, rescaled so 50 is the reference average and 15 points is one standard deviation. A hollow marker rests on a single benchmark.

Price against capability

The shaded corner holds anything better and cheaper. Prices blend input and output 3 to 1.

49 models from the past year score higher on Math for less: GPT-6.1 Terra, Claude Haiku 5.5, Muse Spark 1.3 and 46 more.

$0.1$0.3$1$3$10$3020406080GPT-6.1 Terra: 76, $2 per 1MDeepSeek V4.1 Flash 1017: 63, $0.26 per 1MMuse Spark Open: 60, $2 per 1MClaude Haiku 5.5: 66, $0.2 per 1MMistral Large 4: 54, $2.06 per 1MGemini 4 Argon: 75, $4 per 1MGPT-6.1 Sol: 78, $4 per 1MClaude Sonnet 5.5: 75, $4 per 1MGPT-6 Sol: 74, $4 per 1MGPT-6 Luna: 63, $0.2 per 1MClaude Opus 5.5: 77, $8 per 1MGrok 4.7: 55, $3 per 1MDeepSeek V4.1 Flash: 60, $0.21 per 1MGPT-6 Astra: 78, $20 per 1MMuse Spark 1.3: 65, $2 per 1MGemini 3.8 Flash: 58, $1.5 per 1MClaude Fable 5.1: 76, $20 per 1MGLM-5.3-Flash: 47, $0.24 per 1MDeepSeek V4 Flash Vision Exp: 48, $0.32 per 1MQwen3.8 27B: 42, $1.12 per 1MGLM-5.3: 56, $2.15 per 1MGemini 3.7 Flash: 62, $1.5 per 1MDeepSeek V4 Pro 0813: 60, $0.99 per 1MGrok 4.6: 60, $3 per 1MMuse Spark 1.2: 56, $2 per 1MQwen3.8 Max: 62, $3 per 1MDeepSeek V4 Flash 0731: 55, $0.15 per 1MClaude Opus 5: 73, $10 per 1MGemini 3.6 Flash: 52, $1.5 per 1MGemini 3.5 Flash Lite: 35, $0.85 per 1MKimi K3: 61, $6 per 1MQwen3.7 Flash: 48, $0.055 per 1MGPT-5.6 Terra: 70, $4.5 per 1MGPT-5.6 Sol: 73, $8 per 1MGPT-5.6 Luna: 63, $0.45 per 1MGrok 4.5: 55, $3 per 1MClaude Sonnet 5: 62, $4 per 1MGLM-5.2: 54, $2.15 per 1MKimi K2.7 Code: 46, $1.71 per 1MClaude Fable 5: 75, $20 per 1MQwen3.7 Plus: 54, $0.7 per 1MClaude Opus 4.8: 67, $10 per 1MQwen3.7 Max: 53, $3.75 per 1MGemini 3.5 Flash: 54, $3.38 per 1MGPT-5.5 Instant: 42, $11.2 per 1MDeepSeek V4 Pro: 49, $1.19 per 1MDeepSeek V4 Flash: 27, $0.11 per 1MGPT-5.5 Pro: 72, $67.5 per 1MGPT-5.5: 68, $11.2 per 1MQwen3.6 27B: 45, $1.35 per 1MKimi K2.6: 49, $1.71 per 1MGrok 4.3: 39, $1.56 per 1MGrok Build 0.1: 23, $1.25 per 1MClaude Opus 4.7: 60, $10 per 1MQwen3.6 35B-A3B: 49, $0.84 per 1MMuse Spark 1.1: 50, $2 per 1MGLM-5.1: 51, $2.15 per 1MGemma 4 31B IT: 58, $0.25 per 1MQwen3.6 Plus: 37, $1.12 per 1MGPT-5.4 nano: 48, $0.46 per 1MGPT-5.4 mini: 44, $1.69 per 1MGPT-5.4 Pro: 67, $67.5 per 1MGPT-5.4: 64, $5.62 per 1MGemini 3.1 Flash Lite: 49, $0.56 per 1MQwen3.5 Flash: 47, $0.18 per 1MQwen3.5 9B: 53, $0.19 per 1MQwen3.5 35B-A3B: 56, $0.69 per 1MGemini 3.1 Pro Preview: 55, $4.5 per 1MClaude Sonnet 4.6: 54, $6 per 1MQwen3.5 Plus: 63, $0.9 per 1MQwen3.5 397B-A17B: 52, $1.35 per 1MGLM-5: 60, $1.55 per 1MClaude Opus 4.6: 57, $10 per 1MGLM-4.7: 48, $1 per 1MGemini 3 Flash Preview: 50, $1.12 per 1MGPT-5.2 Pro: 61, $57.8 per 1MGPT-5.2 Codex: 51, $4.81 per 1MGPT-5.2: 54, $4.81 per 1MDeepSeek V3.2: 64, $0.32 per 1MClaude Opus 4.5: 51, $10 per 1MGPT-5.1: 64, $3.44 per 1MGPT-5.1 Codex Max: 37, $3.44 per 1MGPT-5.1 Codex MaxPrice per 1M tokens →↑ Math$0.1$1$1020406080GPT-6.1 Terra: 76, $2 per 1MDeepSeek V4.1 Flash 1017: 63, $0.26 per 1MMuse Spark Open: 60, $2 per 1MClaude Haiku 5.5: 66, $0.2 per 1MMistral Large 4: 54, $2.06 per 1MGemini 4 Argon: 75, $4 per 1MGPT-6.1 Sol: 78, $4 per 1MClaude Sonnet 5.5: 75, $4 per 1MGPT-6 Sol: 74, $4 per 1MGPT-6 Luna: 63, $0.2 per 1MClaude Opus 5.5: 77, $8 per 1MGrok 4.7: 55, $3 per 1MDeepSeek V4.1 Flash: 60, $0.21 per 1MGPT-6 Astra: 78, $20 per 1MMuse Spark 1.3: 65, $2 per 1MGemini 3.8 Flash: 58, $1.5 per 1MClaude Fable 5.1: 76, $20 per 1MGLM-5.3-Flash: 47, $0.24 per 1MDeepSeek V4 Flash Vision Exp: 48, $0.32 per 1MQwen3.8 27B: 42, $1.12 per 1MGLM-5.3: 56, $2.15 per 1MGemini 3.7 Flash: 62, $1.5 per 1MDeepSeek V4 Pro 0813: 60, $0.99 per 1MGrok 4.6: 60, $3 per 1MMuse Spark 1.2: 56, $2 per 1MQwen3.8 Max: 62, $3 per 1MDeepSeek V4 Flash 0731: 55, $0.15 per 1MClaude Opus 5: 73, $10 per 1MGemini 3.6 Flash: 52, $1.5 per 1MGemini 3.5 Flash Lite: 35, $0.85 per 1MKimi K3: 61, $6 per 1MQwen3.7 Flash: 48, $0.055 per 1MGPT-5.6 Terra: 70, $4.5 per 1MGPT-5.6 Sol: 73, $8 per 1MGPT-5.6 Luna: 63, $0.45 per 1MGrok 4.5: 55, $3 per 1MClaude Sonnet 5: 62, $4 per 1MGLM-5.2: 54, $2.15 per 1MKimi K2.7 Code: 46, $1.71 per 1MClaude Fable 5: 75, $20 per 1MQwen3.7 Plus: 54, $0.7 per 1MClaude Opus 4.8: 67, $10 per 1MQwen3.7 Max: 53, $3.75 per 1MGemini 3.5 Flash: 54, $3.38 per 1MGPT-5.5 Instant: 42, $11.2 per 1MDeepSeek V4 Pro: 49, $1.19 per 1MDeepSeek V4 Flash: 27, $0.11 per 1MGPT-5.5 Pro: 72, $67.5 per 1MGPT-5.5: 68, $11.2 per 1MQwen3.6 27B: 45, $1.35 per 1MKimi K2.6: 49, $1.71 per 1MGrok 4.3: 39, $1.56 per 1MGrok Build 0.1: 23, $1.25 per 1MClaude Opus 4.7: 60, $10 per 1MQwen3.6 35B-A3B: 49, $0.84 per 1MMuse Spark 1.1: 50, $2 per 1MGLM-5.1: 51, $2.15 per 1MGemma 4 31B IT: 58, $0.25 per 1MQwen3.6 Plus: 37, $1.12 per 1MGPT-5.4 nano: 48, $0.46 per 1MGPT-5.4 mini: 44, $1.69 per 1MGPT-5.4 Pro: 67, $67.5 per 1MGPT-5.4: 64, $5.62 per 1MGemini 3.1 Flash Lite: 49, $0.56 per 1MQwen3.5 Flash: 47, $0.18 per 1MQwen3.5 9B: 53, $0.19 per 1MQwen3.5 35B-A3B: 56, $0.69 per 1MGemini 3.1 Pro Preview: 55, $4.5 per 1MClaude Sonnet 4.6: 54, $6 per 1MQwen3.5 Plus: 63, $0.9 per 1MQwen3.5 397B-A17B: 52, $1.35 per 1MGLM-5: 60, $1.55 per 1MClaude Opus 4.6: 57, $10 per 1MGLM-4.7: 48, $1 per 1MGemini 3 Flash Preview: 50, $1.12 per 1MGPT-5.2 Pro: 61, $57.8 per 1MGPT-5.2 Codex: 51, $4.81 per 1MGPT-5.2: 54, $4.81 per 1MDeepSeek V3.2: 64, $0.32 per 1MClaude Opus 4.5: 51, $10 per 1MGPT-5.1: 64, $3.44 per 1MGPT-5.1 Codex Max: 37, $3.44 per 1MGPT-5.1 Codex MaxPrice per 1M tokens →↑ Math

OpenRouter $1.25 / $10 · Cached input $0.12

Epoch benchmark boards

Best result on each board it has run. The tick marks the leader.

METR Time Horizons
71%#10 of 42
Terminal Bench
60%#15 of 50
ProofBench
9%#68 of 81

OpenAI's past year

24 release days in the past year, about one every 15 days. The next is expected around Nov 8, 2026. Forecasts ↗

NovDecJanFebMarAprMayJunJulAugSepOctNov

Specifications

RELEASE DATENov 13, 2025
WEIGHTSClosed weights
CONTEXT WINDOW400K
MAX OUTPUT128K
REASONINGNot listed
TOOL CALLINGNot listed
INPUTStext, image/jpeg, image/png, image/gif, image/webp
OUTPUTStext

Models.dev record ↗

Specifications and prices from Models.dev; availability and limits may differ by provider. Benchmarks from Epoch AI (CC BY 4.0), LiveBench and the other sources named above.