Claude Sonnet 4 vs GPT-5.6 Terra
Side-by-side API pricing and Artificial Analysis performance for Claude Sonnet 4 (Anthropic) and GPT-5.6 Terra (OpenAI). Green cells mark the better value in each row.
Prices updated Sep 17, 2026, 1:13 PM UTC · refreshed hourly
| Claude Sonnet 4 Anthropic | GPT-5.6 Terra OpenAI | |
|---|---|---|
| Pricing | ||
| Input $/1M | $3.00 | $2.00 |
| Output $/1M | $15.00 | $12.00 |
| Blended $/1M (3:1) | $6.00 | $4.50 |
| RAG example (30K in / 2K out) | $0.12 | $0.084 |
| Quality & speed | ||
| Intelligence Index | — | 42.3 |
| Coding Index | 37.6 | 76.7 |
| Agentic Index | — | 43.7 |
| Output speed (tok/s) | — | 101 |
| Time to first token | — | 163.05s |
| Specs | ||
| Context window | 1M | 1.05M |
| Input modalities | image, text, file | file, image, text |
FAQ
Which is cheaper, Claude Sonnet 4 or GPT-5.6 Terra?
GPT-5.6 Terra has the lower blended API price at $4.50 per 1M tokens (3:1 input:output mix), versus $6.00 for the other model. Prices are live from OpenRouter and refresh about hourly.
Which is better for RAG workloads?
For a typical RAG request (30K input / 2K output tokens), GPT-5.6 Terra costs about $0.084 per request versus $0.12. Also compare context windows: Claude Sonnet 4 offers 1M and GPT-5.6 Terra offers 1.05M.
Which scores higher on Artificial Analysis benchmarks?
GPT-5.6 Terra leads on the Artificial Analysis Intelligence Index (42.3 vs —). Check coding and agentic indices on this page for workload-specific tradeoffs.