GPT-5.5 is an OpenAI model, 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)
970 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
45.6
Coding Index
74.9
Reasoning
GPQA Diamond
Graduate-level scientific reasoning
93.5%
Better than 97% of models compared
HLE
Humanity's Last Exam
45.8%
Better than 96% 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
84.3%
Better than 99% of models compared
GDPval-AA
Economically valuable tasks
27.9%
CritPt
Research-level physics reasoning
1.4%
Coding
Terminal-Bench Hard
Agentic coding and terminal use
60.6%
Better than 98% 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 Sep 7, 2026
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