GPT-6 Luna
OpenAI
An OpenAI sixth-generation model released 22 September 2026 as gpt-6-luna, alongside GPT-6 Sol. OpenAI describes it as its most efficient model for focused, high-volume tasks, priced 50% below GPT-5.6 Luna's promotional pricing. It takes text and image input and returns text, with a 1,050,000 token context window, 128,000 maximum output tokens and an 18 May 2026 knowledge cutoff. Reasoning effort can be set to none, low, medium (the default), high, xhigh or max. Available in the API and in ChatGPT Work and Codex; OpenAI says Free and Go users can reach it in the desktop app.
Pricing & specs verifiedSource: vendor documentation · checked Sep 23, 2026
Pricing
$0.10 / $0.50 per 1M tokens
Context
1,050,000 tokens
LMArena Elo
Not rated
Overall rank
Not ranked
Key Features
Reasoning Vision Long Context Tool Use 128k Max Output Prompt Caching Computer Use
Full Specifications
$0.10 / $0.50 per 1M tokens | |
|---|---|
| Identity | |
| Developer | OpenAI |
| Released | Sep 2026 |
| Status | GA |
| Licence | Proprietary |
| Self-hostable | No |
| Cost | |
| Blended $/1M tokensinput × 0.75 + output × 0.25 | $0.200 / 1M tokens |
| Input price | $0.100 / 1M tokens |
| Output price | $0.500 / 1M tokens |
| Cached input | $0.01 per 1M tokens |
| Batch discount | 50% (Batch and Flex) |
| Capacity | |
| Context window | 1,050,000 tokens |
| Max output | 128k tokens |
| Long-context surcharge | Prompts over 272K input tokens: 2x input and cache rates, 1.5x output |
| Capability | |
| Vision in | Yes |
| Audio in | No |
| Function calling | Yes |
| Structured output | Yes |
| Extended reasoning | Yes |
| Web search | Yes |
| Code execution | Yes |
| Access | |
| API | Yes |
| Chat app | Yes |
| Fine-tuning | No |