Claude Haiku 4.5 is Anthropic’s fastest and most efficient model, delivering near-frontier intelligence at a fraction of the cost and latency of larger Claude models. Matching Claude Sonnet 4’s performance across reasoning, coding, and comp…
Model details →Anthropic: Claude Haiku 4.5 vs OpenAI: GPT-5.1-Codex-Mini
OpenAI: GPT-5.1-Codex-Mini wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
GPT-5.1-Codex-Mini is a smaller and faster version of GPT-5.1-Codex
Model details →Side-by-side comparison
| Capability | Anthropic: Claude Haiku 4.5 | OpenAI: GPT-5.1-Codex-Mini | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 200K | 400K | 🏆 OpenAI: GPT-5.1-Codex-Mini |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $1.00 | $0.25 | 🏆 OpenAI: GPT-5.1-Codex-Mini |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $5.00 | $2.00 | 🏆 OpenAI: GPT-5.1-Codex-Mini |
| 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 Haiku 4.5 better than OpenAI: GPT-5.1-Codex-Mini?
OpenAI: GPT-5.1-Codex-Mini wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
What's the price difference between Anthropic: Claude Haiku 4.5 and OpenAI: GPT-5.1-Codex-Mini?
Input: $1.00 vs $0.25 per 1M tokens. Output: $5.00 vs $2.00 per 1M tokens.
What context windows do Anthropic: Claude Haiku 4.5 and OpenAI: GPT-5.1-Codex-Mini support?
Anthropic: Claude Haiku 4.5 supports up to 200K tokens. OpenAI: GPT-5.1-Codex-Mini supports up to 400K tokens.
Do both Anthropic: Claude Haiku 4.5 and OpenAI: GPT-5.1-Codex-Mini support tool calling?
Anthropic: Claude Haiku 4.5: yes. OpenAI: GPT-5.1-Codex-Mini: yes.