[whatmodel.sh](../../README.md) / GPT-5.6 Luna # GPT-5.6 Luna OpenAI · released 2026-07 · closed weights **score 75.0** ±0.5 · #34 of 732 · from 38 benchmark results across 10 sources Score within the [LMArena (text)](https://whatmodel.sh/?set=lmarena-text&score=set) comparison set only. ## What it's good at ● marks GPT-5.6 Luna among every model on that task or test, worst to best.
task                vs the others         rank  counts  tests
agent tasks         ▁▁▃▆█▄▅▅▄●▂▁    #44 of 313     21%      9
coding              ▁▁▁▃▅▇█▇▅●▃▁    #49 of 469     10%      4
chat & writing      ▁▁▁▃▆▄▆█▆▇●▃   #54 of 402*    2.6%      1
math                ▁▁▃▅█▆▄█▄●▁▁    #17 of 431     39%      3
vision & documents  ▁▁▂▂▁▃▄▂▆▇●▄    #41 of 153    5.4%      5
web search          ▁▁▁▅▄█●▄·▁·▁    #24 of 84*    2.1%      1
agent tasks · #44 of 313 · 21% of its score Trails [GLM-5.2](glm-5-2.md), [GLM-5.3-Flash](glm-5-3-flash.md), [Grok 4.7](grok-4-7.md) here, though they rank lower overall.
test                                     result  vs the others in its run  difficulty            counts  why
Arena Agent (October 2026 aggrega…  -0.0233 IPS  ▁▁▁▃▃●█▁▂▂▁▁ beats 20/59  avg -0.379 IPS          6.6%  sharp
Terminal-Bench 4.0                        17.3%  █▅●▅▅·▅▃▃▅▅▅ beats 5/20   very hard · avg 0.5%    2.5%  sharp
SWE-bench Pro (split unspecified)…        62.7%  ▂·▁▁▁▁▂▃█●▂▁ beats 46/58  very hard · avg 4.9%    2.4%  sharp · at its level
Terminal-Bench 2.1 (maker)                84.7%  ▁·▁·▁▁▄▃▆█▅● beats 52/63  hard · avg 23%          2.3%  sharp
BrowseComp (maker)                        83.3%  ▄··●▄··▄·▄█▄ beats 2/8    medium · avg 38%        2.1%  typical
Toolathlon (Tool Decathlon) (make…        53.4%  ▃··▃··▃··▃●▅ beats 5/8    very hard · avg 13%     1.7%  at its level
DeepSWE v1.1 (resolved) (maker)           67.2%  ●··▃▃····▃·▃ beats 2/6    hard · avg 22%          1.4%  at its level
Agents' Last Exam (metric/harness…        50.3%  ▂·▂·█▄▂·▂▂●▄ beats 11/14  very hard · avg 12%     0.9%  at its level
KlinikeBench strict pass@1 (333 i…         7.5%  ▁▁·▁▁▁▁●▃█▅█ beats 7/27   very hard · avg 2.4%    0.8%  typical
coding · #49 of 469 · 10% of its score Beats [GPT-5.5](gpt-5-5.md), [GPT-5.4](gpt-5-4.md) here, though they rank higher overall. Trails [Qwen3.8 27B](qwen3-8-27b.md), [GLM-5.2](glm-5-2.md), [Gemini 3.6 Flash](gemini-3-6-flash.md) here, though they rank lower overall.
test                                result  vs the others in its run   difficulty            counts  why
Arena WebDev (Code Arena)           1518.9  ▁▁▃▂▅█▃●▅▅▁▂ beats 77/129  avg 981                 4.5%  sharp
SWE-bench Pro (split unspecified)…   62.7%  ▂·▁▁▁▁▂▃█●▂▁ beats 46/58   very hard · avg 4.9%    2.4%  sharp · at its level
Luau Leetcode fully solved (Torpe…   72.6%  ▁▁▁▁·▁▂▃▅●█▇ beats 24/49   hard · avg 17%          1.7%  sharp
DeepSWE v1.1 (resolved) (maker)      67.2%  ●··▃▃····▃·▃ beats 2/6     hard · avg 22%          1.4%  at its level
chat & writing · #54 of 402 · 2.6% of its score Beats [MiMo-V2.6-Flash (309B-A15B)](mimo-v2-6-flash.md), [Claude Haiku 5.5](claude-haiku-5-5.md), [GPT-6 Luna](gpt-6-luna.md) here, though they rank higher overall. Trails [Claude Sonnet 4.5](claude-sonnet-4-5.md), [Gemini 3.5 Flash-Lite](gemini-3-5-flash-lite.md), [MiMo-V2.5-Pro (1T-A42B)](mimo-v2-5-pro.md) here, though they rank lower overall.
test            result  vs the others in its run    difficulty  counts  why
LMArena (text)  1453.0  ▁▁▁▂▃▃▃▆▆▇●▃ beats 323/385  avg 1260      2.6%  blunt
math · #17 of 431 · 39% of its score Beats [DeepSeek V4.1 Flash 1017](deepseek-v4-1-flash-1017.md), [Qwen3.8 Max (2.4T-A95B)](qwen3-8-2-4t-a95b.md), [Claude Opus 4.8](claude-opus-4-8.md) here, though they rank higher overall.
test                       result  vs the others in its run    difficulty            counts  why
FrontierMath tier 4 v2      61.0%  ▁▂▁▂█▅●▃▂▁▁▁ beats 53/67    very hard · avg 0.1%     22%  sharp · at its level · several runs
FrontierMath tiers 1–3 v2   82.1%  ▂··▁▁▃▄▄█▆●▃ beats 72/86    very hard · avg 1.2%     17%  sharp · at its level · several runs
OTIS mock AIME 2024–2025    98.3%  ▃▃▄▃▃▃▇▇█▃●▅ beats 176/197  very hard · avg 7.2%    0.3%  sharp · maxed out · noisy
vision & documents · #41 of 153 · 5.4% of its score Beats [MiMo-V2.6-Pro](mimo-v2-6-pro.md), [MiMo-V2.6-Flash (309B-A15B)](mimo-v2-6-flash.md), [DeepSeek V4.1 Flash](deepseek-v4-1-flash.md) here, though they rank higher overall. Trails [Qwen3.6 Flash](qwen3-6-flash.md), [Gemini 3.5 Flash-Lite](gemini-3-5-flash-lite.md), [Qwen3.6 Plus](qwen3-6-plus.md) here, though they rank lower overall.
test                                result  vs the others in its run    difficulty           counts  why
Arena vision (style controlled)     1256.6  ▁▁▂▂▂▂▃▄▅▅●▇ beats 113/152  avg 1061               1.7%  blunt
MMMU Pro (maker)                     78.4%  ▅·····▃·●·█▃ beats 3/7      hard · avg 40%         1.7%  typical
Arena document (style controlled)   1462.0  ▁▁▃▃▄▃▇●▅▇▄▅ beats 19/37    avg 1331               0.9%  blunt
SciDocBench scientific-document w…   50.6%  ▃▃···●▃▅▃·▃▅ beats 4/11     hard · avg 25%         0.9%  blunt · at its level
SpaceCast-Bench predictive spatia…   46.6%  ▃·▅▃▅▃··●··█ beats 7/11     very hard · avg 33%    0.3%  at its level · noisy
web search · #24 of 84 · 2.1% of its score Beats [GPT-5.5](gpt-5-5.md), [Claude Opus 4.8](claude-opus-4-8.md), [GPT-5.4](gpt-5-4.md) here, though they rank higher overall. Trails [GPT-4o mini (2024-07-18)](gpt-4o-mini-2024-07-18.md), [Mistral Small 3.1 24B (2503)](mistral-small-3-1.md), [GPT-4o (2024-08-06)](gpt-4o-2024-08-06.md) here, though they rank lower overall.
test                result  vs the others in its run  difficulty        counts  why
BrowseComp (maker)   83.3%  ▄··●▄··▄·▄█▄ beats 2/8    medium · avg 38%    2.1%  typical
other tests (16)
test                                result  vs the others in its run    difficulty            counts  why
Furniture Assembly (Epoch)           42.5%  █▆▆▆●▂▆▂▂▂▂▅ beats 17/32    very hard · avg 1.2%    4.4%  sharp · at its level
Mystery Game Puzzles (Epoch)         21.0%  █··▂▃●▄█▂▄▂▁ beats 37/77    very hard · avg 9.4%    4.3%  sharp · at its level · noisy
KMMLU-HARD (Daekeun Kim, zero-sho…   75.8%  █···▁▁▁▂▃·●▂ beats 19/23    very hard · avg 29%     3.0%  sharp · at its level
Chess Puzzles (Epoch)                40.0%  █▁▁▁▁▂▃▃●▂▁▁ beats 121/137  very hard · avg 5.8%    2.5%  sharp · at its level · noisy
GPQA Diamond                         91.6%  ▁▁▁▁▂▄▆▄▅▇●▅ beats 186/211  hard · avg 39%          1.6%  sharp
CLIcK Korean (Daekeun Kim)           91.5%  ▆▄▄▄█▄▂·▄●·▄ beats 19/23    medium · avg 56%        1.4%  typical
KoBALT-700 (Daekeun Kim)             77.0%  ▄▄●·····▄··▄ beats 3/5      hard · avg 39%          1.2%  typical
KMMLU-Pro (Daekeun Kim)              85.5%  ▄·▄●·····▄·▄ beats 2/5      medium · avg 43%        1.0%  typical
HAE-RAE 1.0 (Daekeun Kim)            93.2%  ▄▄▄▂▂█▂▄▂█●▄ beats 20/22    medium · avg 61%        1.0%  maxed out
SimpleQA Verified                    41.0%  ▁▁▃▂▃▃▆●█▄▂▅ beats 35/81    very hard · avg 8.0%    1.0%  at its level
Icelandic LLM Leaderboard average…   53.9%  ▁▁▃▂▂▄▁▃▄●▄█ beats 23/38    very hard · avg 14%     1.0%  at its level
HealthBench Professional (maker)     55.7%  ▄·▄··●▄·▄█·█ beats 2/8      hard · avg 20%          1.0%  blunt · at its level
MuSR Korean (Daekeun Kim)            71.5%  ●·····███·██ beats 0/5      medium · avg 45%        0.7%  typical
RobloxQA v2.0 multiple choice (To…   95.8%  ▁▁▃▁█▄▃●▆▂▂▂ beats 32/49    easy · avg 77%          0.6%  maxed out
HealthBench Hard (maker)             31.4%  ▂··▂····▂●·█ beats 4/8      very hard · avg 9.6%    0.6%  blunt · at its level
HealthBench (maker)                  55.4%  ▃·▃·····●▃▃▅ beats 2/8      hard · avg 24%          0.6%  blunt · at its level
## How the score was worked out Each result implies a score on its own, after adjusting for how hard that test is and who ran it. The model's score is their weighted average, with a small pull toward the middle for thinly tested models. Each test's weight is its *counts* column above; here it is added up by who ran the tests. [Method](../method.md)
source                                    results  share of the score
Epoch AI                                        8   36% ▇▇▇▇
OpenAI vendor-reported benchmark scores…       12   32% ▇▇▇▇
LMArena leaderboard dataset                     5   16% ▇▇
Daekeun Kim Korean LLM benchmark runs           6    8% ▇
Terminal-Bench 4.0 official leaderboard…        1    3% ▇
Roblox LLM Leaderboard                          2    2% ▇
Miðeind Icelandic LLM Leaderboard               1    1% ▇
SciDocBench: A Workflow-Centered Benchm…        1    1% ▇
KlinikeBench: Evaluating Language Model…        1    1% ▇
SpaceCast-Bench: Evaluating Predictive …        1    0% ▇
prior: pull toward the middle                        0% ▇
weighted average                                   = 75.0
Licences: Epoch AI ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · LMArena leaderboard dataset ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · Daekeun Kim Korean LLM benchmark runs ([MIT](../../licenses/korean-personal-benchmark-runs-MIT.txt)) · Terminal-Bench 4.0 official leaderboard submissions ([Apache-2.0](../../licenses/terminal-bench-leaderboard-submissions-Apache-2.0.txt)) · Roblox LLM Leaderboard ([MIT](../../licenses/roblox-llm-leaderboard-MIT.txt)) · Miðeind Icelandic LLM Leaderboard ([CC BY 4.0](../../licenses/mideind-icelandic-llm-leaderboard-CC-BY-4.0.txt)) · SciDocBench: A Workflow-Centered Benchmark and Data Pipeline for Scientific Document Understanding ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · KlinikeBench: Evaluating Language Models Beyond Diagnostic Accuracy ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) · SpaceCast-Bench: Evaluating Predictive Spatial Reasoning in Vision-Language Models ([CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)) ## How to run it ### Through an API api (OpenAI) · $0.45/M blended · $0.2 in / $1.2 out per 1M tokens · [platform.openai.com](https://platform.openai.com/docs/models) [price source](https://github.com/anomalyco/models.dev/blob/a668908cfe7073faa0363699486fc41a3ff52412/providers/openai/models/gpt-5.6-luna.toml): Standard base token rate from models.dev. Provider-specific tiers, long-context surcharges, caching and promotions may differ. · [context source](https://github.com/anomalyco/models.dev/blob/a668908cfe7073faa0363699486fc41a3ff52412/models/openai/gpt-5.6-luna.toml) [interactive version](https://whatmodel.sh/model/gpt-5-6-luna) · [JSON](https://whatmodel.sh/api?format=json&all=1)