GPT-5.6 Lunaon Krater.ai
GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series.
Released July 9, 2026
Specifications
GPT-5.6 Luna at a glance
Context
1.1M tokens
Max output
128K tokens
Input
File, Image, Text
Output
Text
Input price
$0.20 / 1M
Output price
$1.20 / 1M
Knowledge cutoff
2026-02-16
Krater rank
#1
Is ChatGPT down?
ChatGPT not loading? Krater checks OpenAI every 5 minutes and shows what to switch to while it is down.
Live ChatGPT statusCapabilities
What it is good at
Catalog capabilities
- Accepts image input
- Generates text responses
- Supports tool calling
- Supports structured outputs
Good for
Benchmarks
Catalog data, not Krater benchmarks.
Coding index score
71.4
Agentic index score
42.1
Intelligence index score
37.3
Compare
Compare GPT-5.6 Luna
GPT-5.6 Luna vs GPT-5.6 Luna Pro
GPT-5.6 Luna Pro is the same underlying model as GPT-5.6 Luna, served with reasoning.mode set to pro for higher-quality responses on complex tasks.
Open comparisonGPT-5.6 Luna vs GPT-6 Astra
GPT-6 Astra is OpenAI's flagship model for demanding end-to-end work.
Open comparisonGPT-5.6 Luna vs GPT-5.6 Sol Pro
GPT-5.6 Sol Pro is the same underlying model as GPT-5.6 Sol, served with reasoning.mode set to pro for higher-quality responses on complex tasks.
Open comparisonFAQ
Questions about GPT-5.6 Luna
Clear answers based on the model catalog and Krater access.