Claude Opus 5 vs GPT-5.6
Two flagships at identical input pricing with completely different characters. I compare rates, test results, and write plainly which I'd choose for what.
as of: 11 November 2026 · prices refreshed daily
Rates from OpenRouter, updated daily along with AI cost calculator.
Test results
| Test | Claude Opus 5 | GPT-5.6 Sol | source |
|---|---|---|---|
| Frontier-Bench v0.1 | 43.3% | 34.4% | Anthropic's launch materials |
| ARC-AGI-3 | 30.2% | 7.8% | Anthropic's launch materials |
| SWE-bench Pro | 79.2% | no data | Anthropic's launch materials |
When Claude Opus 5
I'd pick Opus 5 for coding and long agentic work: in the toughest tests from Anthropic's launch materials it holds a clear edge, and output costs one-sixth less, which with reasoning models that write many "thinking" tokens makes a real difference on the bill.
When GPT-5.6 Sol
GPT-5.6 Sol has the ChatGPT ecosystem behind it: if your team lives in that environment, has plugins, history and habits, switching for benchmarks alone rarely pays off. The Terra variant at half the rate is also the most sensible mid-tier choice at OpenAI.
My verdict
At identical input pricing, output and tasks decide: for code and agents Opus 5, for work in the OpenAI ecosystem and lighter tasks GPT-5.6 Terra instead of Sol. The table numbers come from Anthropic's materials, so treat them as strong guidance, not verdict.
Frequently Asked Questions
Which is cheaper: Claude Opus 5 or GPT-5.6 Sol?
Claude Opus 5 costs 5 / 25 $ per million tokens (input / output), while GPT-5.6 Sol costs 4 / 20 $. Rates come from OpenRouter and are updated daily; the real cost of a task also depends on how many reasoning tokens the model consumes.
Are these benchmarks reliable?
Every result in the table has a cited source. Some numbers come from manufacturers' materials, measured in their own environment and highlighting their strengths - I treat them as guidance, not verdict. The fairest test remains a week of work on your own tasks.
Where can I check the real cost of working with both models?
In the AI cost calculator on this site, I convert the rates of all tracked models daily into three real tasks: an article, a hundred chat queries, and an hour of agent work - in USD.
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