Compare · ModelsLive · 2 picked · head to head
Claude Opus 5 vs GPT-5.5 Pro
Side by side · benchmarks, pricing, and signals you can act on.
Winner summary
GPT-5.5 Pro wins on 1/1 benchmarks
GPT-5.5 Pro wins 1 of 1 shared benchmarks. Leads in knowledge.
Category leads
knowledge·GPT-5.5 Pro
Hype vs Reality
Attention vs performance
Claude Opus 5
#21 by perf·#6 by attention
GPT-5.5 Pro
#1 by perf·#4 by attention
Best value
Claude Opus 5
5.5x better value than GPT-5.5 Pro
Claude Opus 5
4.6 pts/$
$15.00/M
GPT-5.5 Pro
0.8 pts/$
$105.00/M
Vendor risk
Who is behind the model
Anthropic
$965.0B·Tier 1
OpenAI
$840.0B·Tier 1
Head to head
1 benchmark · 2 models
Claude Opus 5GPT-5.5 Pro
GPQA diamond
GPT-5.5 Pro leads by +2.4
Graduate-Level Google-Proof QA (Diamond set) · expert-crafted questions in physics, biology, and chemistry that are difficult even for domain PhDs.
Claude Opus 5
91.8
GPT-5.5 Pro
94.2
Full benchmark table
| Benchmark | Claude Opus 5 | GPT-5.5 Pro |
|---|---|---|
GPQA diamond Graduate-Level Google-Proof QA (Diamond set) · expert-crafted questions in physics, biology, and chemistry that are difficult even for domain PhDs. | 91.8 | 94.2 |
Pricing · per 1M tokens · projected $/mo at 10M tokens
| Model | Input | Output | Context | Projected $/mo |
|---|---|---|---|---|
| $5.00 | $25.00 | 1.0M tokens (~500 books) | $100.00 | |
| $30.00 | $180.00 | 400K tokens (~200 books) | $675.00 |