Head-to-head
Claude Sonnet 5.5 vs GPT-5.6 Terra
As of October 25, 2026, Claude Sonnet 5.5 leads GPT-5.6 Terra on the Analyzer Index, 86.7 to 82.3.
Normalized scores are min-maxed per benchmark across all models we track (0–100). Open the interactive compare view to add benchmarks to the radar chart or pull in more models.
Claude Sonnet 5.5
AnthropicGPT-5.6 Terra
OpenAI| At a glance | Claude Sonnet 5.5 | GPT-5.6 Terra |
|---|---|---|
| Analyzer Index | 86.7 (5/13) | 82.3 (5/13) |
| Blended price | $4.00/M | $2.25/M |
| Cheapest host | maker's API | maker's API |
| Context | 1.0M | 1.1M |
| Output speed | 101 tok/s | 89 tok/s |
| Time to first token | 1.06 s | 2.00 s |
| Benchmark | Claude Sonnet 5.5 | GPT-5.6 Terra |
|---|---|---|
Chatbot Arena Elo Arena | ||
Output Speed Speed | ||
Time to First Token TTFT | ||
SimpleQA Verified SimpleQA | ||
OTIS Mock AIME 2024-2025 OTIS AIME | ||
Humanity's Last Exam HLE | — | |
ARC-AGI 2 ARC-AGI 2 | — | |
Frontier Composite Frontier | ||
Output Stability Stability | ||
Format Adherence Format | ||
Recovery Rate Recovery | ||
API Success Rate API OK | ||
Safety Handling Safety |
Methodology matches the main AI Model Analyzer About page.