GPT-5.6 Terra is the balanced model in OpenAI's GPT-5.6 series, positioned between flagship Sol and cost-efficient Luna. It is suited for everyday coding, reasoning, agentic work, and general professional tasks.
Added Jul 9, 2026
Context Window
1.1M
Max Output
128K
Input Price (Auto)
$2.00/1M
Output Price (Auto)
$12.00/1M
Cache Read (Auto)
$0.20/1M
Capabilities
Benchmarks
Benchmarks
Performance metrics and benchmarks
Sourced from Artificial Analysis.
Intelligence Index
42.1
Coding Index
76.7
Agentic Index
43.2
Agentic work
AutomationBench-AA
Workflow automation with guardrail penalties
59.6%
Better than 87% of models compared
Harvey LAB-AA
Legal agentic work criterion pass rate
85.2%
Better than 48% of models compared
AA-Briefcase
Agentic knowledge work (Elo)
1334 Elo
Better than 76% of models compared
GDPval-AA v2
Economically valuable tasks (Elo)
1432 Elo
Better than 81% of models compared
Document reasoning
GDP.pdf
Professional PDF reasoning: all-pass rate
24.0%
Better than 85% of models compared
AA-LCR v1.1
Long context reasoning with updated grading
83.0%
Better than 96% of models compared
MLCR-AA
Medical long-context reasoning
31.7%
Better than 83% of models compared
Reasoning
HLE
Humanity's Last Exam
42.9%
Better than 93% of models compared
IFBench
Instruction-following benchmark
71.2%
Better than 87% of models compared
CritPt
Research-level physics reasoning
30.0%
Coding
Terminal-Bench v4.0
Practical coding and terminal tasks
35.4%
Better than 88% of models compared
SciCode
Python programming for scientific computing
55.0%
Better than 77% of models compared
Knowledge
AA-Omniscience Accuracy
Proportion of correctly answered questions
46.8%
AA-Omniscience Hallucination Rate
Rate of incorrect answers among non-correct responses
87.9%
Legacy benchmarks
GPQA Diamond (legacy)
Graduate-level scientific reasoning
92.5%
Better than 94% of models compared
Terminal-Bench Hard (legacy)
Agentic coding and terminal use
57.6%
Better than 97% of models compared
T²-Bench Telecom (legacy)
Conversational AI agents in dual-control scenarios
86.3%
Better than 79% of models compared
AA-LCR (unversioned / legacy)
Long context reasoning evaluation
83.0%
Better than 96% of models compared
GDPval-AA (unversioned / legacy)
Economically valuable tasks
46.6%
Last updated Sep 28, 2026
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GPT 6 Sol
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GPT 6 Sol Pro
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