Claude Opus 4.8 vs GPT-5.6 Terra Pro
How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for Claude Opus 4.8 and GPT-5.6 Terra Pro.
Claude Opus 4.8
Claude Opus 4.8 is Anthropic's most capable generally available model in the Opus family. It supports text, image, and file inputs with text output, with reasoning support and a 1M-token...
GPT-5.6 Terra Pro
GPT-5.6 Terra Pro is the same underlying model as [GPT-5.6 Terra](https://openrouter.ai/openai/gpt-5.6-terra), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode
Technical Specifications
| Specification | Claude Opus 4.8 | GPT-5.6 Terra Pro |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Context Window | 1,000,000 tokens | 1,050,000 tokens |
| Agent Suitability | 97/100 | N/A |
| Time to First Token (TTFT) | 520 ms | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | beta | beta |
| API Available | Yes | Yes |
| Released Date | 2026-05-27 | 2026-07-09 |
API Pricing Comparison
Input Price per Million Tokens
Claude Opus 4.8
$5.00
GPT-5.6 Terra Pro
$2.50
Output Price per Million Tokens
Claude Opus 4.8
$25.00
GPT-5.6 Terra Pro
$15.00
Want to test both models live?
Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
Claude Opus 4.8 Quirks & Gotchas
- ▸Best-in-class for autonomous code repair and multi-agent orchestration
- ▸Preview model — API may introduce breaking changes without notice
GPT-5.6 Terra Pro Quirks & Gotchas
No developer gotchas reported.