Claude Sonnet 4 significantly enhances the capabilities of its predecessor, Sonnet 3.7, excelling in both coding and reasoning tasks with improved precision and controllability. Achieving state-of-the-art performance on SWE-bench (72.7%), S…
Model details →Anthropic: Claude Sonnet 4 vs OpenAI: GPT-5.1-Codex-Max
OpenAI: GPT-5.1-Codex-Max wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks. It is based on an updated version of the 5.1 reasoning stack and trained on agentic workflows spanning software e…
Model details →Side-by-side comparison
| Capability | Anthropic: Claude Sonnet 4 | OpenAI: GPT-5.1-Codex-Max | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 200K | 400K | 🏆 OpenAI: GPT-5.1-Codex-Max |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $3.00 | $1.25 | 🏆 OpenAI: GPT-5.1-Codex-Max |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $15.00 | $10.00 | 🏆 OpenAI: GPT-5.1-Codex-Max |
| 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 Sonnet 4 better than OpenAI: GPT-5.1-Codex-Max?
OpenAI: GPT-5.1-Codex-Max wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
What's the price difference between Anthropic: Claude Sonnet 4 and OpenAI: GPT-5.1-Codex-Max?
Input: $3.00 vs $1.25 per 1M tokens. Output: $15.00 vs $10.00 per 1M tokens.
What context windows do Anthropic: Claude Sonnet 4 and OpenAI: GPT-5.1-Codex-Max support?
Anthropic: Claude Sonnet 4 supports up to 200K tokens. OpenAI: GPT-5.1-Codex-Max supports up to 400K tokens.
Do both Anthropic: Claude Sonnet 4 and OpenAI: GPT-5.1-Codex-Max support tool calling?
Anthropic: Claude Sonnet 4: yes. OpenAI: GPT-5.1-Codex-Max: yes.