GPT-5.6 Luna
Budgetby OpenAI
GPT-5.6 Luna is the fastest and cheapest model in the GPT-5.6 family, previewed June 26, 2026. Pricing is $1 per million input tokens and $6 per million output, with a 1 million token context window. Like its siblings, Luna entered as a limited preview to roughly 20 pre-approved organizations under a US Government arrangement, with general availability planned in the coming weeks. OpenAI is positioning it for high-volume, latency-sensitive workloads where Sol-level reasoning is not required.
Input Price
$1.00
per 1M tokens
Output Price
$6.00
per 1M tokens
Context Window
1M
tokens
Released
2026-06
API access
Capabilities
Key Strengths
- ✓Lowest pricing in the GPT-5.6 family ($1/$6 per 1M)
- ✓1M token context window
- ✓Frontier-family lineage at budget-tier economics
- ✓Reasoning, vision, tool use, and code included
Best For
- ▸High-volume chat and classification
- ▸Cost-sensitive coding assistants
- ▸Real-time tool-augmented workflows
- ▸Latency-sensitive customer-facing applications
Pricing Details
Input tokens
$1.00
per 1M tokens
Output tokens
$6.00
per 1M tokens
Estimated cost per 1K requests
$4.00
~1K input + ~500 output tokens avg
Prices are subject to change. Check the official documentation for current pricing. See the cost calculator for detailed estimates.
Related Models
GPT-5.6 Sol
FlagshipOpenAI
$5.00 in / $30.00 out
GPT-5.6 Terra
Mid-tierOpenAI
$2.50 in / $15.00 out
GPT-5.5
FlagshipOpenAI
$5.00 in / $30.00 out
GPT-4o
FlagshipOpenAI
$2.50 in / $10.00 out
GPT-4o-mini
BudgetOpenAI
$0.15 in / $0.60 out
o1
FlagshipOpenAI
$15.00 in / $60.00 out
o3-mini
Mid-tierOpenAI
$1.10 in / $4.40 out
Claude Haiku 4.5
BudgetAnthropic
$0.80 in / $4.00 out
Gemini 2.0 Flash
Budget$0.10 in / $0.40 out
Gemini 3.1 Flash-Lite
Budget$0.25 in / $1.50 out
Mistral Small
BudgetMistral
$0.10 in / $0.30 out