GPT-5.6 Luna vs GPT-6 Luna
At a Glance
| Compare |  GPT-5.6 LunaOpenAI | GPT-6 LunaOpenAI |
|---|---|---|
| Intelligence, Cost, and Efficiency | ||
| IntelligenceHigher is better · MM Intelligence v4.4 | UnrankedNot in the 57-model eligible cohort | #29 of 5742.3 score · 3/3 sources · complete |
| CostLower is better · Published-token output estimate | UnrankedNot in the 27-model eligible cohort | #4 of 27$0.018 per LiveBench case |
| EfficiencyHigher is better · MM Efficiency v1.9 | UnrankedNot in the 27-model eligible cohort | #10 of 2752.8 score · 3/3 sources · complete |
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $0.20Openai ↗ · Sep 3, 2026 | $0.10Openai ↗ · Sep 22, 2026 |
| Output priceFrom · USD / 1M tokens | $1.20Openai ↗ · Sep 3, 2026 | $0.50Openai ↗ · Sep 22, 2026 |
| Context windowMaximum documented tokens | 1,050K | 1,050K |
| Model facts checked | Aug 28, 2026View model evidence → | Sep 22, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
| Benchmark | GPT-5.6 Luna | GPT-6 Luna |
|---|---|---|
| ARC-AGI-1verified-v1-613c385b0c93 · verified_score · leader | 90.67100% of row best · percent · GPT-5.6 Luna 2026-07-30 (Max) | 86.6796% of row best · percent · GPT-6 Luna (Max) |
| ARC-AGI-2verified-v2-be40992860f9 · verified_score · leader | 59.58100% of row best · percent · GPT-5.6 Luna 2026-07-30 (Max) | 59.31100% of row best · percent · GPT-6 Luna (Max) |
| LMArena Text Arenatext-2026-10-15-a64ca3b12b6e · arena_rating · leader | 1,430.66100% of row best · rating · gpt-5.6-luna-xhigh; 95% CI [1426.38028671, 1434.93119450]; votes 41109; rank 93 | 1,391.6397% of row best · rating · gpt-6-luna-max; 95% CI [1387.01005073, 1396.24774606]; votes 49617; rank 166 |
| LiveBench2026-06-25-90f8d44da965 · overall · leader | 77.05100% of row best · percent · gpt-5.6-luna-max · 21,799 output tokens / case | 75.8498% of row best · percent · gpt-6-luna-max · 35,869 output tokens / case |
| ToneBench2026-10-17-10-task-e9c76358afb2 · overall_score · unverified | 78.83100% of row best · points · GPT-5.6 Luna (ultra) · 19,621 output tokens / case | 78.1999% of row best · points · GPT-6 Luna (max) · 6,595 output tokens / case |
| Overall ResultCounted from the protocol-matched rows above | 4 benchmark winsOverall lead | 0 benchmark wins |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Side-by-Side Facts
| Field | GPT-5.6 Luna | GPT-6 Luna |
|---|---|---|
| Developer | OpenAI | OpenAI |
| Family | Gpt 5 6 | Gpt 6 |
| Model | GPT-5.6 Luna | GPT-6 Luna |
| Version | GPT-5.6 Luna | GPT-6 Luna |
| Lifecycle | active | active |
| Released | Unknown | 2026-09-22 |
| Knowledge cutoff | 2026-02-16 | 2026-05-18 |
| Input modalities | Text, Image | Text, Image |
| Output modalities | Text | Text |
| Context window | 1,050K | 1,050K |
| Total parameters | Unknown | Unknown |
| Active parameters | Unknown | Unknown |
| License | Unknown | Unknown |
| Open weights | No | No |
| API available | Yes | Yes |
| Self-hostable | No | No |
| Provider access | Openai (Standard), Openrouter (Standard) | Openai (Standard), Openrouter (Standard) |
| Capabilities | chat, generation, reasoning, tools | chat, computer-use, generation, reasoning, tools |
| Default snapshot | Unknown | gpt-6-luna |
| Maximum input tokens | Unknown | 922000 |
| Reasoning effort | Unknown | none, low, medium, high, xhigh, max |
| Supported API routes | Unknown | v1/responses, v1/chat/completions, v1/batch |
GPT-5.6 Luna Capabilities
GPT-6 Luna Capabilities
Related Comparisons
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|---|---|---|---|
GPT-5.6 LunaOpenAI | vs | GPT-6 AstraOpenAI | family variantsimage, text |
 MiniMax-M3MiniMax | vs | GPT-5.6 LunaOpenAI | cross-developer peersimage, text |
Claude Sonnet 5Anthropic | vs | GPT-5.6 LunaOpenAI | cross-developer peersimage, text |
Claude Fable 5Anthropic | vs | GPT-5.6 LunaOpenAI | cross-developer peersimage, text |
Claude Opus 4.8Anthropic | vs | GPT-5.6 LunaOpenAI | cross-developer peersimage, text |
 Gemini 2.5 ProGoogle DeepMind | vs | GPT-5.6 LunaOpenAI | cross-developer peerstext |
| vs | GPT-5.6 LunaOpenAI | cross-developer peersimage, text | |
| vs | GPT-5.6 LunaOpenAI | cross-developer peersimage, text | |
GPT-4.1 NanoOpenAI | vs | GPT-5.6 LunaOpenAI | family variantsimage, text |
GPT-5.4 MiniOpenAI | vs | GPT-5.6 LunaOpenAI | family variantsimage, text |
GPT-5.4 ProOpenAI | vs | GPT-5.6 LunaOpenAI | family variantsimage, text |
Primary Evidence
Sources and Freshness
Questions
GPT-5.6 Luna vs GPT-6 Luna FAQs
Is GPT-5.6 Luna or GPT-6 Luna better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both GPT-5.6 Luna and GPT-6 Luna, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, GPT-5.6 Luna or GPT-6 Luna?+
GPT-5.6 Luna is $0.20 and GPT-6 Luna is $0.10 per million tokens, so GPT-6 Luna is cheaper on this metric. GPT-5.6 Luna is $1.20 and GPT-6 Luna is $0.50 per million tokens, so GPT-6 Luna is cheaper on this metric.
Which has a larger context window, GPT-5.6 Luna or GPT-6 Luna?+
Both models have the same sourced context window: 1,050,000 tokens each.
Which performs better in benchmarks, GPT-5.6 Luna or GPT-6 Luna?+
GPT-5.6 Luna leads the current overall benchmark count. The result uses 4 protocol-matched benchmarks from 3 publishers; it is not a universal quality score.
Can GPT-5.6 Luna or GPT-6 Luna be self-hosted?+
Both models have the same sourced self-hosting status: unsupported. GPT-5.6 Luna is not marked open weight; GPT-6 Luna is not marked open weight.
Can GPT-5.6 Luna and GPT-6 Luna understand images?+
GPT-5.6 Luna is documented with image input; GPT-6 Luna is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, GPT-5.6 Luna or GPT-6 Luna?+
Both models have the same sourced maximum output: 128,000 tokens each.
Do GPT-5.6 Luna and GPT-6 Luna support reasoning and tool use?+
GPT-5.6 Luna: reasoning, tool calling, and image input. GPT-6 Luna: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, GPT-5.6 Luna or GPT-6 Luna?+
GPT-5.6 Luna has 2 sourced provider routes; GPT-6 Luna has 2, a tie.
Which offers better value, GPT-5.6 Luna or GPT-6 Luna?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.