GPT-5.6 Luna

by OpenAI

GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume, latency-sensitive tasks such as chat, classification, and lightweight agentic workflows, providing capable reasoning for...

Quick Facts

Provider

OpenAI

Model ID

openai/gpt-5.6-luna

Modality

Text and Image and File to Text

Tier

Premium

Last Updated

2026-07-22

Released

2026-07-09

Context Length

1050K tokens

Tokenizer

GPT

Input Price

$1.00/M

Output Price

$6.00/M

When To Use GPT-5.6 Luna

Best for

  • Reasoning-heavy questions and step-by-step analysis
  • Research, summarization, and document work
  • Image understanding, screenshots, and visual questions
  • Comparing OpenAI responses against other leading AI models

Not ideal for

  • High-volume casual chats where you want to conserve premium credits
  • Native image generation workflows
  • Voice, speech, or audio transcription workflows

Input & Output

Accepts

text
image
file

Generates

text

Pricing

All prices are per 1 million tokens

Input

$1.00/M

Output

$6.00/M

Cache Read

$0.10/M

Cache Write

$1.25/M

Web Search

$10000.00/M

Capabilities

  • Natural language understanding and generation
  • Image analysis and understanding
  • Advanced reasoning and problem-solving
  • Long context window for extended conversations

Example Prompts

Solve this problem step by step, then summarize the final answer in one paragraph.

Summarize these notes into key findings, risks, and recommended next steps.

Analyze this screenshot and explain what is happening, including any UI issues.

Compare how GPT-5.6 Luna and two other models answer this prompt.

Use GPT-5.6 Luna to produce a concise answer, then list assumptions and tradeoffs.

Supported Parameters

include_reasoningmax_completion_tokensmax_tokensreasoningreasoning_effortresponse_formatseedstructured_outputstool_choicetools

Compare and Use GPT-5.6 Luna

Frequently Asked Questions

Try GPT-5.6 Luna In Related Workflows

Model pages work best when they connect to real tasks. Use these bots and utilities to test GPT-5.6 Luna against coding, research, and model-selection workflows.

Try GPT-5.6 Luna

Use GPT-5.6 Luna on RyddleAI

Access GPT-5.6 Luna with a RyddleAI subscription.

Compare GPT-5.6 Luna With Alternatives

Use these nearby models to test whether GPT-5.6 Luna is the right choice for your prompt, budget, and model family preference.

AlternativeProviderTierWhy comparePage
GPT-5.6 Luna ProOpenaiPremiumAnother OpenAI model to compare within the same provider familyView model
GPT-5.6 Terra ProOpenaiPremiumAnother OpenAI model to compare within the same provider familyView model
Gemini 3.6 FlashGooglePremiumSame tier alternative from another providerView model
Gemini 3.5 Flash LiteGooglePremiumSame tier alternative from another providerView model