Claude Opus 4.7 (Fast) vs GPT-5.1-Codex
A side-by-side comparison of two multimodal models — real specs, pricing, strengths and weaknesses, and a clear verdict on which to choose. Kept current by our agents.
Quick verdict: which should you choose?
Choose Claude Opus 4.7 (Fast) if you need
- ✓Choose Claude Opus 4.7 (Fast) if you need higher intelligence_index of 53.5 and nuanced careful reasoning.
- ✓Choose Claude Opus 4.7 (Fast) if you need 1M context for effective large-context handling.
- ✓Choose Claude Opus 4.7 (Fast) if you need strong safety alignment on multimodal tasks.
- ✓Choose Claude Opus 4.7 (Fast) if you need the fast variant for reduced latency on massive inputs.
Choose GPT-5.1-Codex if you need
- ✓Choose GPT-5.1-Codex if you need output_speed of 188.36 t/s for extended coding workflows.
- ✓Choose GPT-5.1-Codex if you need output_price of $10 per 1M tokens.
- ✓Choose GPT-5.1-Codex if you need specialized performance on software development with visual context.
- ✓Choose GPT-5.1-Codex if you need handling of very large inputs without losing coherence at lower cost.
Verdict
Claude Opus 4.7 (Fast) leads on intelligence (53.5 vs 34.7) and context length (1M vs 400k) with stronger safety alignment and nuanced reasoning, while GPT-5.1-Codex dominates on speed (188.36 t/s vs 52.47) and price ($10 vs $150 per 1M). Claude suits careful large-context multimodal work; GPT-5.1-Codex excels in fast, cost-effective coding workflows with visual inputs.
Claude Opus 4.7 (Fast) vs GPT-5.1-Codex: side by side
| Spec | Claude Opus 4.7 (Fast) | GPT-5.1-Codex | Winner |
|---|---|---|---|
| Intelligence | 53.5 | 34.7 | Claude Opus 4.7 (Fast) |
| Output speed | 52 t/s | 188 t/s | GPT-5.1-Codex |
| Output price | $150.00/1M | $10.00/1M | GPT-5.1-Codex |
| Context | 1000K | 400K | Claude Opus 4.7 (Fast) |
| Params | — | — | Tie |
| Provider | Anthropic | OpenAI | Tie |
Detailed analysis
Intelligence
Winner: Claude Opus 4.7 (Fast)Claude Opus 4.7 (Fast) scores 53.5 on intelligence_index compared to GPT-5.1-Codex at 34.7. This supports stronger nuanced reasoning and safety alignment for Claude on multimodal tasks.
Speed
Winner: GPT-5.1-CodexGPT-5.1-Codex delivers 188.36 tokens per second versus Claude Opus 4.7 (Fast) at 52.47 t/s. The speed advantage favors GPT-5.1-Codex for high-volume or latency-sensitive coding work.
Pricing
Winner: GPT-5.1-CodexGPT-5.1-Codex costs $10 per 1M output tokens while Claude Opus 4.7 (Fast) costs $150 per 1M. GPT-5.1-Codex provides a clear cost edge for extended usage.
Context Length
Winner: Claude Opus 4.7 (Fast)Claude Opus 4.7 (Fast) supports 1M context tokens versus GPT-5.1-Codex at 400k. This gives Claude the advantage for effective large-context multimodal handling.
Claude Opus 4.7 (Fast)
Pros
- +Strong safety alignment
- +Nuanced and careful reasoning
- +Effective large-context handling
Cons
- –May decline edge-case or risky requests
- –Multimodal tasks can increase response time
- –Large context usage remains resource-heavy
GPT-5.1-Codex
Pros
- +Strong performance on extended coding workflows
- +Effective integration of visual context with code
- +Handles very large inputs without losing coherence
Cons
- –Limited to text and image inputs only
- –High computational cost for maximum context
- –May require careful prompt engineering for complex tasks
Summary: Claude Opus 4.7 (Fast) vs GPT-5.1-Codex
Select Claude Opus 4.7 (Fast) when intelligence, safety, and maximum context matter most despite higher cost and slower speed. Choose GPT-5.1-Codex for faster, cheaper operation on coding and visual integration tasks. The models serve different priorities within multimodal use cases.
Frequently asked questions
Claude Opus 4.7 (Fast) is better on intelligence and context; GPT-5.1-Codex is better on speed and price. Neither is universally superior.