Claude Opus 5.5 vs GPT-6.1 Terra Pro
API pricing, context, and independently measured performance, side by side. GPT-6.1 Terra Pro starts 75% cheaper on input than Claude Opus 5.5 at list prices.
Claude Opus 5.5
Anthropic · released Sep 22, 2026
Best input$4.00 / MTok
Best output$20.00 / MTok
Context1M
Providers12
Fastest measured3s° TTFT · 149 tok/s
VisionToolsReasoningStructured outputPrompt caching
GPT-6.1 Terra Pro
OpenAI · released Oct 26, 2026
Best input$1.00 / MTok
Best output$5.00 / MTok
Context1.05M
Providers3
Fastest measured—
VisionToolsReasoningStructured outputPrompt caching
Cheapest providers, measuredUSD / MTOK
| MODEL | PROVIDER | INPUT | OUTPUT | TTFT | TPS | SMOKE |
|---|---|---|---|---|---|---|
| Claude Opus 5.5 |  Amazon Bedrock | $4.00 | $20.00 | 5.7s° | 173° tok/s | — |
| Claude Opus 5.5 |  Azure | $4.00 | $20.00 | 3s° | 149° tok/s | — |
| Claude Opus 5.5 |  Google | $4.00 | $20.00 | 4.2s° | 913° tok/s | — |
| GPT-6.1 Terra Pro |  OpenAI | $1.00 | $5.00 | — | — | — |
TTFT/TPS: ModelIndex-measured medians (P50, trailing 21d) · chat10k profile (~10K in / 200 out) · ° = measured via OpenRouter routing (adds a hop) · SMOKE: of 5 programmatic capability probes passed · methodology v1.1 — full details on each model page