OpenAI · model passport
OpenAI: GPT-5.6 Luna
gpt-5-6-luna- Cloud only
- Proprietary licence
- 1,050,000 context
- Released 2026-09-13(first seen on LMArena)
- Overall · LMArena
- 1,453#66 of 396
- Best percentile
- 89.0AIME (math)
- Cohort standing
- 63.9median 60.3
What the data says
Benchmarked on 15 of 27 tracked axes. Every figure below is the model's own published result on that board.
Strongest axes
- 89 pct — AIME (math) (98.3%)
- 88.2 pct — GPQA Diamond (91.6%)
Uneven: 62.9 percentile points between its best and worst axis — 89 pct on AIME (math) versus 26.1 pct on Terminal-Bench 4.0.
- AIME (math)89 pct98.3%Verify →
- GPQA Diamond88.2 pct91.6%Verify →
- Overall83.6 pct1,453Verify →
- Instruction following83.3 pct1,443Verify →
- Coding83.1 pct1,501Verify →
- Hard prompts83.1 pct1,474Verify →
- Factuality Arena76.7 pct1,461Verify →
- Vision Arena74 pct1,258Verify →
- WebDev Arena66.9 pct1,519Verify →
- ARC-AGI-265.2 pct59.5%Verify →
- Document Arena52.6 pct1,462Verify →
- SimpleBench46 pct46.8%Verify →
- SimpleQA Verified45.1 pct41.0%Verify →
- Agent Arena36.4 pct-0.018Verify →
- Terminal-Bench 4.026.1 pct17.3%Verify →
- Search ArenaNot benchmarked
- FrontierMathNot benchmarked
- Humanity's Last ExamNot benchmarked
- LiveBenchNot benchmarked
- BFCL v4 (function calling)Not benchmarked
- SWE-bench Verified (live board)Not benchmarked
- MMLU-Pro (Artificial Analysis)Not benchmarked
- LiveCodeBench (Artificial Analysis)Not benchmarked
- IFBench (Artificial Analysis)Not benchmarked
- HHEM Hallucination (Vectara)Not benchmarked
- SWE-bench VerifiedNot benchmarked
- Terminal-BenchNot benchmarked
Percentiles are the model's standing within each board's own population. Axes marked "not benchmarked" have no published result for this model — that is an absence of data, not a low score.
How to run it
Use it hosted
openai/gpt-5.6-lunaAPI parameters this endpoint supports
Example request
curl https://openrouter.ai/api/v1/chat/completions \
-H "Authorization: Bearer $OPENROUTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model":"openai/gpt-5.6-luna","messages":[{"role":"user","content":"Hello"}]}'Identifiers, limits and prices are synced from the upstream source shown above. Any field we haven't synced is left out entirely rather than guessed.
gpt-5.6-luna-xhigh stands at 63.9 (raw mean 66.6) — measured on 15 of 27 axes.
gpt-5.6-luna-xhigh stands at 63.9 versus a cohort median of 60.3 across 176 models released within 180 days — above the peer median.
gpt-5.6-luna-xhigh scores in the 89th percentile on AIME (math).
gpt-5.6-luna-xhigh scores at percentile 88.2 on GPQA Diamond.
gpt-5.6-luna-xhigh ranks between #30 and #146 across 6 built-in weightings — best under "Reasoning", worst under "All sources".
Every claim is a computed fact from the current board data, phrased by a low-temperature model call and rejected by a validation gate if any number is not in the source row. How the leaderboards work →