Claude Opus 4.5 is Anthropic’s frontier reasoning model optimized for complex software engineering, agentic workflows, and long-horizon computer use. It offers strong multimodal capabilities, competitive performance across real-world coding…
Model details →Anthropic: Claude Opus 4.5 (batch) vs OpenAI: GPT-5.1 (batch)
OpenAI: GPT-5.1 (batch) wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
GPT-5.1 is the latest frontier-grade model in the GPT-5 series, offering stronger general-purpose reasoning, improved instruction adherence, and a more natural conversational style compared to GPT-5. It uses adaptive reasoning...
Model details →Side-by-side comparison
| Capability | Anthropic: Claude Opus 4.5 (batch) | OpenAI: GPT-5.1 (batch) | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 200K | 400K | 🏆 OpenAI: GPT-5.1 (batch) |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $2.50 | $0.63 | 🏆 OpenAI: GPT-5.1 (batch) |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $12.50 | $5.00 | 🏆 OpenAI: GPT-5.1 (batch) |
| Tool / function calling First-class support for emitting structured tool calls. | Yes | Yes | Tie |
| Vision input Accepts image inputs alongside text. | Yes | Yes | Tie |
| Reasoning mode Internal chain-of-thought / extended-thinking support. | Yes | Yes | Tie |
Frequently asked questions
Is Anthropic: Claude Opus 4.5 (batch) better than OpenAI: GPT-5.1 (batch)?
OpenAI: GPT-5.1 (batch) wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
What's the price difference between Anthropic: Claude Opus 4.5 (batch) and OpenAI: GPT-5.1 (batch)?
Input: $2.50 vs $0.63 per 1M tokens. Output: $12.50 vs $5.00 per 1M tokens.
What context windows do Anthropic: Claude Opus 4.5 (batch) and OpenAI: GPT-5.1 (batch) support?
Anthropic: Claude Opus 4.5 (batch) supports up to 200K tokens. OpenAI: GPT-5.1 (batch) supports up to 400K tokens.
Do both Anthropic: Claude Opus 4.5 (batch) and OpenAI: GPT-5.1 (batch) support tool calling?
Anthropic: Claude Opus 4.5 (batch): yes. OpenAI: GPT-5.1 (batch): yes.
Compare Anthropic: Claude Opus 4.5 (batch) with other models
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