Choose Claude Opus 5 if
- ✓ You need maximum reasoning depth
- ✓ You want complex agent workflows with strong instruction following
- ✓ Your evaluation favors Claude's output style
Head to head · OpenRouter
Claude Opus 5 vs OpenAI GPT-5.6 Terra
Claude Opus 5 has lower output pricing than GPT-5.6 Terra, while Terra emphasizes strong multimodal and file reasoning.
Quick verdict
Claude Opus 5 is a strong choice for difficult reasoning, complex agent chains and high-stakes code. GPT-5.6 Terra is better when your workload leans heavily on multimodal input and long, file-heavy tasks.
Side-by-side comparison
| Field | Claude Opus 5 | OpenAI GPT-5.6 Terra |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Context window | 1M tokens | 1.05M tokens |
| Input / 1M | $5.00 | $2.00 |
| Output / 1M | $25.00 | $12.00 |
| Modalities | Text, Vision, Files | Text, Vision, Files |
| Best for | Overall, Agents, Coding | Overall, Multimodal, Agents |
Source
openrouter.ai/api/v1/models Verified 2026-10-16 Cost estimates
| Workload | Input | Output | Claude Opus 5 | OpenAI GPT-5.6 Terra |
|---|---|---|---|---|
| Quick test | 20,000 | 5,000 | $0.225 | $0.100 |
| Product chat month | 500,000 | 125,000 | $5.63 | $2.50 |
| Document batch | 5,000,000 | 1,000,000 | $50.00 | $22.00 |
Estimates use list input/output prices and exclude cache discounts, provider surcharges and tool fees.
Choose OpenAI GPT-5.6 Terra if
- ✓ Your prompts rely on images, files or mixed media
- ✓ You want a long-context multimodal workflow
- ✓ Your product already uses OpenAI tool interfaces
FAQ
Is Claude Opus 5 cheaper than OpenAI GPT-5.6 Terra?
Claude Opus 5 costs $5.00 input and $25.00 output per 1M tokens. OpenAI GPT-5.6 Terra costs $2.00 input and $12.00 output per 1M tokens.
Which model has the larger context window?
Claude Opus 5 offers 1M tokens; OpenAI GPT-5.6 Terra offers 1.05M tokens. Provider-specific limits can vary by route.
Which one should I choose?
Claude Opus 5 is a strong choice for difficult reasoning, complex agent chains and high-stakes code. GPT-5.6 Terra is better when your workload leans heavily on multimodal input and long, file-heavy tasks.
Claude Opus 5 details OpenAI GPT-5.6 Terra details Estimate monthly cost
Pricing and context data are based on a 2026-10-16 snapshot. Provider limits and pricing can change; verify on OpenRouter before production.