Fast-mode variant of [Opus 5](/anthropic/claude-opus-5) - identical capabilities with higher output speed at 2x pricing relative to regular Opus 5. Learn more in Anthropic's docs: https://platform.claude.com/docs/en/build-with-claude/fast-…
Model details →Claude Opus 5 (Fast) vs OpenAI: GPT Chat Latest
Claude Opus 5 (Fast) and OpenAI: GPT Chat Latest are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
GPT Chat Latest points to OpenAI's stable API alias `chat-latest` that always resolves to the latest Instant chat model used in ChatGPT. As OpenAI rolls out new Instant model updates...
Model details →Side-by-side comparison
| Capability | Claude Opus 5 (Fast) | OpenAI: GPT Chat Latest | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 1M | 400K | 🏆 Claude Opus 5 (Fast) |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $10.00 | $5.00 | 🏆 OpenAI: GPT Chat Latest |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $50.00 | $30.00 | 🏆 OpenAI: GPT Chat Latest |
| 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 | — | 🏆 Claude Opus 5 (Fast) |
Frequently asked questions
Is Claude Opus 5 (Fast) better than OpenAI: GPT Chat Latest?
Claude Opus 5 (Fast) and OpenAI: GPT Chat Latest are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
What's the price difference between Claude Opus 5 (Fast) and OpenAI: GPT Chat Latest?
Input: $10.00 vs $5.00 per 1M tokens. Output: $50.00 vs $30.00 per 1M tokens.
What context windows do Claude Opus 5 (Fast) and OpenAI: GPT Chat Latest support?
Claude Opus 5 (Fast) supports up to 1M tokens. OpenAI: GPT Chat Latest supports up to 400K tokens.
Do both Claude Opus 5 (Fast) and OpenAI: GPT Chat Latest support tool calling?
Claude Opus 5 (Fast): yes. OpenAI: GPT Chat Latest: yes.
Compare Claude Opus 5 (Fast) with other models
vs Anthropic Claude Haiku Latestvs Anthropic Claude Sonnet Latestvs Anthropic: Claude Fable Latestvs Anthropic: Claude Opus Latest