Glimmer Index
Plus $4/mo

GPT-5.6 Luna

OpenAI · Released Jul 9, 2026 · Closed weights

Cost-efficient GPT-5.6 model for fast, high-volume workloads

Strongest at
Math
Top 29% of the past year's models · 5 of 5 benchmarks
Price per 1M tokens
$0.2 / $1.2
input / output · OpenAI
Context window
1.05M
tokens in · 128K out
Lab announcement ↗Open in the timeline

Capability profile

Scored against 91 models released in the past year. 50 is the average model; further out is better.

This modelMedian of the past year
5090Median of the past yearCoding: 56 · Top 42%Writing: 53 · Better than 40%Reading & documents: 44 · Better than 30%Reasoning: 57 · Better than 43%Math: 63 · Top 29%Science: 54 · Better than 15%Visual reasoning: 51 · Better than 38%Computer use: 55 · Better than 17%CodingWritingReadingReasoningMathScienceVisionComputer use
Coding56Top 42%
Writing53Better than 40%
Reading & documents44Better than 30%
Reasoning57Better than 43%
Math63Top 29%
Science54Better than 15%
Visual reasoning51Better than 38%
Computer use55Better than 17%
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 dot rests on a single benchmark.

Price against capability

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

3 models from the past year score higher on Math for less: Claude Haiku 5.5, DeepSeek V3.2, GPT-6 Luna.

$0.1$0.3$1$3$10$3020406080GPT-6.1 Terra: 76, $2 per 1MDeepSeek V4.1 Flash 1017: 63, $0.52 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 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, $0.18 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 Codex Max: 37, $3.44 per 1MGPT-5.1: 64, $3.44 per 1MGPT-5.6 Luna: 63, $0.45 per 1MGPT-5.6 LunaPrice per 1M tokens →↑ Math$0.1$1$1020406080GPT-6.1 Terra: 76, $2 per 1MDeepSeek V4.1 Flash 1017: 63, $0.52 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 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, $0.18 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 Codex Max: 37, $3.44 per 1MGPT-5.1: 64, $3.44 per 1MGPT-5.6 Luna: 63, $0.45 per 1MGPT-5.6 LunaPrice per 1M tokens →↑ Math

OpenAI $0.2 / $1.2 · OpenRouter $0.2 / $1.2 · Cached input $0.02

The GPT-6 Luna line

2 releases in the GPT-6 Luna line.

GPT-5.6 LunaJul 9, 202675dGPT-6 LunaSep 22, 2026

A newer release is out: GPT-6 Luna.

ECI STANDING#29 of 270
SCORE156.5154.19–159.26 CI
FRONTIER LAGLaunched 5.1 months behindScores about what GPT-5.3 Codex did in February 2026.
SCORES LIKE THESE MODELSClaude Opus 4.7Anthropic · Apr 2026156.79GPT-6 LunaOpenAI · Sep 2026156.75Grok 4.6xAI · Aug 2026156.57GPT-5.2 ProOpenAI · Dec 2025156.33
Full Epoch Capabilities Index ranking ↗

Epoch benchmark boards

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

GPQA diamond
92%#29 of 234
OTIS Mock AIME 2024-2025
98%#27 of 216
FrontierMath-Tiers-1-3-v2-Private
82%#17 of 90
Balrog
46%#8 of 39
WeirdML
61%#33 of 141
FrontierMath-Tier-4-v2-Private
61%#18 of 72
ProofBench
60%#21 of 81
DTBench
89%#51 of 179
11 more boards
ARC-AGI
88%#33 of 107
ARC-AGI-2
60%#34 of 103
Chess Puzzles
43%#32 of 93
Surface Evolver Bench
62%#9 of 26
Furniture Assembly
42%#17 of 35
Mystery Game Puzzles
21%#44 of 88
SimpleBench
47%#49 of 89
SimpleQA Verified
41%#49 of 85
FrontierCode
40%#27 of 46
APEX-Agents
43%#37 of 51
WeirdML v3
9%#21 of 23

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 DATEJul 9, 2026
WEIGHTSClosed weights
CONTEXT WINDOW1.05M
MAX OUTPUT128K
REASONINGNot listed
TOOL CALLINGNot listed
INPUTStext, image/jpeg, image/png, image/gif, image/webp, application/pdf
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.