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OpenAI · GPT
No. 07
GPT-5.5
OpenAI's flagship: frontier reliability for hard coding and agents at million-token scale.
Field notes
- Context window
- 1.1Mtokens
- Max output
- 128Ktokens
- Input price
- $5/ 1M tokens
- Output price
- $30/ 1M tokens
- Cached input
- $0.50/ 1M tokens
- Modalities
- Text, Image, Pdf
- Knowledge cutoff
- Dec 2025
- Released
- Apr 2026
- Approx. speed
- —
Overview
What this model is
GPT-5.5 is OpenAI's flagship model and, alongside Claude, one of the only genuinely frontier-reliable models for hard, long-horizon agentic coding. It combines strong reasoning, elite tool use, and durable multi-step execution with a roughly 1M-token context. It is the OpenAI default for professional coding, agents, and high-stakes work.
Strengths
- Frontier long-horizon agentic reliability
- Elite real-world coding and tool use
- Strong reasoning across domains
- Roughly 1M-token context window
- Deep prompt-cache discount lowers repeat-prompt cost
Trade-offs
- Expensive output tokens at $30/M
- Slower than mini/nano tiers
- >272K-token prompts incur premium long-context pricing
- No native audio/video input
Best for
- Autonomous coding agents and tool orchestration
- Hard professional and engineering work
- Complex multi-step reasoning
- High-stakes production pipelines
- Long-document analysis across full context
Not ideal for
- Ultra-cheap high-volume classification
- Latency-critical realtime use
Capabilities
Capability profile
Normalized 0–100 scores, comparable across the whole catalog.
- Reasoning
- 96
- Coding
- 95
- Math
- 95
- Writing
- 92
- Knowledge
- 94
- Speed
- 55
- Agentic
- 95
- Vision
- 89
- Multilingual
- 91
- Long Context
- 92
Benchmarks
How it scores
Public benchmark results, with independent third-party results where available. Bars normalize percentages to 100 and Elo ratings to a 1500 ceiling.
Independent index
Artificial Analysis Intelligence Index
Composite of ~9–10 independent evals · Artificial Analysis
55/ 100
BenchmarkResult
Artificial Analysis Intelligence Indexindependent
GeneralArtificial Analysis
55%
SWE-bench Verifiedindependent
CodingSWE-bench
80.6%
SWE-bench Proindependent
CodingSWE-bench Pro
58.6%
GPQA Diamondindependent
ReasoningIndependent aggregators
94%
AIME 2025
MathVendor-reported
95.2%
LiveBenchindependent
GeneralLiveBench
80.7%
Terminal-Bench Hardindependent
AgenticArtificial Analysis
60.6%
DeepSWEindependent
CodingDatacurve
70%
LMArena Eloindependent
GeneralLMArena
1506Elo