GPT-5.5 is OpenAI's smartest and most intuitive model yet, built for agentic coding, computer use, and professional knowledge work with stronger reasoning and token efficiency.
Added Apr 23, 2026
Context Window
1.0M
Max Output
128.0K
Avg output tokens (7d)
1.9K tokens
Input Price (Auto)
$5.00/1M
Output Price (Auto)
$30.00/1M
Cache Read (Auto)
$0.50/1M
Capabilities
Benchmarks
Benchmarks
Performance metrics and benchmarks
Sourced from Artificial Analysis.
Intelligence Index
54.8
Coding Index
74.9
Agentic Index
26.1
Reasoning
GPQA Diamond
Graduate-level scientific reasoning
93.5%
Better than 99% of models compared
HLE
Humanity's Last Exam
44.3%
Better than 99% of models compared
IFBench
Instruction-following benchmark
75.9%
Better than 94% of models compared
T²-Bench Telecom
Conversational AI agents in dual-control scenarios
93.9%
Better than 91% of models compared
AA-LCR
Long context reasoning evaluation
74.3%
Better than 99% of models compared
GDPval-AA
Economically valuable tasks
31.2%
CritPt
Research-level physics reasoning
1.4%
Coding
SciCode
Python programming for scientific computing
56.1%
Better than 99% of models compared
Terminal-Bench Hard
Agentic coding and terminal use
60.6%
Better than 99% of models compared
Knowledge
AA-Omniscience Accuracy
Proportion of correctly answered questions
45.6%
AA-Omniscience Hallucination Rate
Rate of incorrect answers among non-correct responses
92.7%
Last updated Jun 28, 2026
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