GPT-5.6 Luna is the fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume chat, classification, lightweight agentic workflows, and latency-sensitive reasoning tasks.
Added Jul 9, 2026
Context Window
1.1M
Max Output
128.0K
Avg output tokens (7d)
931 tokens
Input Price (Auto)
$0.20/1M
Output Price (Auto)
$1.20/1M
Cache Read (Auto)
$0.020/1M
Capabilities
Benchmarks
Benchmarks
Performance metrics and benchmarks
Sourced from Artificial Analysis.
Intelligence Index
43.4
Coding Index
71.4
Agentic Index
22.2
Reasoning
GPQA Diamond
Graduate-level scientific reasoning
91.1%
Better than 92% of models compared
HLE
Humanity's Last Exam
39.5%
Better than 90% of models compared
AA-LCR
Long context reasoning evaluation
83.7%
Better than 98% of models compared
GDPval-AA
Economically valuable tasks
28.8%
CritPt
Research-level physics reasoning
0.3%
Coding
SciCode
Python programming for scientific computing
53.6%
Better than 65% of models compared
Knowledge
AA-Omniscience Accuracy
Proportion of correctly answered questions
28.6%
AA-Omniscience Hallucination Rate
Rate of incorrect answers among non-correct responses
75.0%
Last updated Sep 7, 2026
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GPT 5.6 Sol Pro
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