Claude Opus 4.5 vs GPT-5.1 Thinking: Specs & Benchmark Comparison
| Characteristic | Claude Opus 4.5 | GPT-5.1 Thinking |
|---|---|---|
| Company | Anthropic | OpenAI |
| Release Date | November 23, 2025 | November 11, 2025 |
| Parameters | — | — |
| Multimodal | Yes | Yes |
| Context (input) | 200K | 256K |
| Context (output) | 64K | 128K |
| Input Price / 1M | $5.00 | $3.00 |
| Output Price / 1M | $25.00 | $12.00 |
| Average Score | 0.9 | 0.9 |
| Benchmarks | ||
| TAU2 Telecom | 1.0 | 1.0 |
| GPQA | 0.9 | 0.9 |
Visual Benchmark Comparison
Claude Opus 4.5
GPT-5.1 Thinking
TAU2 Telecom1.0 vs 1.0
1.0
1.0
GPQA0.9 vs 0.9
0.9
0.9
Verdict
GPT-5.1 Thinking leads in 2 out of 4 comparison categories.
Overall Performance
Both models show comparable average scores: Claude Opus 4.5 — 0.9, GPT-5.1 Thinking — 0.9.
API Cost
GPT-5.1 Thinking is 2.0x cheaper: input $3.00/1M vs $5.00/1M tokens.
Context Window
GPT-5.1 Thinking supports a larger context: 256K vs 200K tokens.
Recency
Both models were released around the same time: 11/23/2025 and 11/11/2025.
More About These Models
Related Comparisons
The Claude Opus 4.5 and GPT-5.1 Thinking comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the Claude Opus 4.5 or GPT-5.1 Thinking page. See also the complete list of AI model comparisons.