GPT-5.6 Luna

OpenAI

GPT-5.6 model optimized for cost-sensitive workloads.

Specs

Model

Family
GPT-5
Variant
5.6 Luna
Weights
Proprietary

Limits

Context
1,050,000 tokens
Max output
128,000 tokens

Modalities

Input
Text Image PDF
Output
Text

Pricing

Input
$0.2 / 1M
Output
$1.2 / 1M
Cache read
$0.02 / 1M
Cache write
$0.25 / 1M

Capabilities

Reasoning
Yes
Reasoning control
Effort levels
Tool calling
Yes
Attachments
Yes

Dates

Released
9 Jul 2026
Knowledge cutoff
16 Feb 2026

Introducing DataBench

DataBench v1: 100 realistic analytical tasks across Q&A and open-ended prompts, run in a synthetic Hex workspace — built because existing analytics benchmarks test "overspecified pub trivia" rather than the vague, directional questions people actually ask.

x.com

Advancing the price-performance frontier with GPT-5.6

By making every layer more efficient, OpenAI is delivering stronger performance per dollar across more enterprise workloads.

OpenAI
openai.com

Getting the most out of GPT-5.6: Sol, Terra, and Luna

Your Codex subscription now comes with 3 main models, Sol, Terra, and Luna, each independently trained and served, with reasoning dials.

Cerebras@cerebras
x.com

GPT-5.6: Frontier intelligence that scales with your ambition

We’re launching the GPT‑5.6 family of models for general availability following our limited preview⁠: our new flagship, Sol, alongside Terra, a balanced model for everyday work, and Luna, our most cost-efficient model.

OpenAI
openai.com

More from OpenAI

All models

GPT-6 Astra

OpenAI

Our most capable model, built for the hardest end-to-end work.

$10 / $50 per 1M · $1 cached 24d ago

GPT-5.6 Terra

OpenAI

GPT-5.6 model that balances intelligence and cost.

$2 / $12 per 1M · $0.2 cached 11w ago

GPT-5.6 Sol

OpenAI

Frontier model for complex professional work.

$4 / $20 per 1M · $0.4 cached 11w ago

Keep up with the tools

An occasional email when notable AI dev tools and models land in the directory. No spam, unsubscribe anytime.