Automated page. Written and translated automatically by AI and checked against the sources by software; no human editor. SI-IQ is an index built from public benchmark results, not an IQ test. How it works

How smart is GPT-5.6 Luna?

130 SI-IQ · 90% interval 127–133
Rank 16 of 80 ranked models · Plausible rank range 11–32

GPT-5.6 Luna is a model from OpenAI, released on Jul 9, 2026. Its SI-IQ is 130 (90% interval 127–133), estimated from 8 benchmark results by 2 independent evaluators. Its strongest area is Math and its weakest is Reasoning.

Facts

Developer: OpenAI
Released: Jul 9, 2026
Access: API access
Benchmarks used: 8 results from 2 evaluators
API price: $0.20 input / $1.20 output per 1M tokens (developer's price list, Oct 18, 2026)
Context window: 922,000 tokens

Ability by area (SI-IQ, 90% interval)

Every benchmark result we used

Each score is one value exactly as the source published it: for Epoch AI the best of its run settings, for OpenRouter the median hosting provider (the developer's own hosting when it ran the test). “Implied SI-IQ” is the ability that this single result points to; the overall SI-IQ is their precision-weighted average.

Benchmark	Area	Score	Implied SI-IQ	Evaluated by	As listed by the source	Retrieved	Source
Chess Puzzles	Reasoning	43.0%	129	Epoch AI	`gpt-5.6-luna_max`	Oct 18, 2026	Epoch AI Benchmarking Hub · data file
Furniture Assembly not in index	Reasoning	42.5%	—	Epoch AI	`gpt-5.6-luna_max`	Oct 18, 2026	Epoch AI Benchmarking Hub · data file
Mystery Game Puzzles	Reasoning	21.0%	115	Epoch AI	`gpt-5.6-luna_max`	Oct 18, 2026	Epoch AI Benchmarking Hub · data file
FrontierMath Tier 4	Math	61.0%	133	Epoch AI	`gpt-5.6-luna_max`	Oct 18, 2026	Epoch AI Benchmarking Hub · data file
FrontierMath Tiers 1–3	Math	82.1%	135	Epoch AI	`gpt-5.6-luna_max`	Oct 18, 2026	Epoch AI Benchmarking Hub · data file
OTIS Mock AIME 2024–2025	Math	98.3%	132	Epoch AI	`gpt-5.6-luna_max`	Oct 18, 2026	Epoch AI Benchmarking Hub · data file
GPQA Diamond	Knowledge	91.6%	128	Epoch AI	`gpt-5.6-luna_max`	Oct 18, 2026	Epoch AI Benchmarking Hub · data file
GPQA Diamond (OpenRouter run)	Knowledge	87.2%	124	OpenRouter	`openai/gpt-5.6-luna-20260709` OpenAI · first-party provider (1 of 3 rows)	Oct 18, 2026	OpenRouter benchmark datasets · data file
SimpleQA Verified	Knowledge	41.0%	120	Epoch AI	`gpt-5.6-luna_max`	Oct 18, 2026	Epoch AI Benchmarking Hub · data file
τ²-bench Airline (OpenRouter run)	Agents	72.3%	124	OpenRouter	`openai/gpt-5.6-luna-20260709` OpenAI · first-party provider (1 of 3 rows)	Oct 18, 2026	OpenRouter benchmark datasets · data file

Models with similar SI-IQ

Model	SI-IQ
GPT-5.4OpenAI	131	GPT-5.6 Luna vs GPT-5.4
GPT-6 LunaOpenAI	130	GPT-5.6 Luna vs GPT-6 Luna
Gemini 3.8 FlashGoogle DeepMind	130	GPT-5.6 Luna vs Gemini 3.8 Flash
Gemini 3.7 FlashGoogle DeepMind	131	GPT-5.6 Luna vs Gemini 3.7 Flash
Claude Haiku 5.5Anthropic	129	GPT-5.6 Luna vs Claude Haiku 5.5

Computed with SI-IQ method version 1.0.0. Read the full methodology

Data sources: Epoch AI, ‘Capabilities & benchmarking’ (CC BY 4.0); API list prices via LiteLLM's price table (MIT); each price links to the developer's pricing page; Source: OpenRouter (openrouter.ai), licensed under CC BY 4.0: reuse and republish with attribution to OpenRouter..