GPT-5.1 Thinking vs Kimi K2-Thinking-0905: Specs & Benchmark Comparison
| Characteristic | GPT-5.1 Thinking | Kimi K2-Thinking-0905 |
|---|---|---|
| Company | OpenAI | Moonshot AI |
| Release Date | November 11, 2025 | September 4, 2025 |
| Parameters | — | 1.0T |
| Multimodal | Yes | No |
| Context (input) | 256K | 262K |
| Context (output) | 128K | 66K |
| Input Price / 1M | $3.00 | $0.60 |
| Output Price / 1M | $12.00 | $2.40 |
| Average Score | 0.9 | 0.9 |
| Benchmarks | ||
| AIME 2025 | 0.9 | 1.0 |
| GPQA | 0.9 | 0.8 |
Visual Benchmark Comparison
GPT-5.1 Thinking
Kimi K2-Thinking-0905
AIME 20250.9 vs 1.0
0.9
1.0
GPQA0.9 vs 0.8
0.9
0.8
Verdict
Kimi K2-Thinking-0905 leads in 2 out of 4 comparison categories.
Overall Performance
Both models show comparable average scores: GPT-5.1 Thinking — 0.9, Kimi K2-Thinking-0905 — 0.9.
API Cost
Kimi K2-Thinking-0905 is 5.0x cheaper: input $0.60/1M vs $3.00/1M tokens.
Context Window
Kimi K2-Thinking-0905 supports a larger context: 262K vs 256K tokens.
Recency
GPT-5.1 Thinking is newer: released 11/11/2025 vs 9/4/2025.
More About These Models
Related Comparisons
The GPT-5.1 Thinking and Kimi K2-Thinking-0905 comparison is updated for 2026. Data includes benchmark results, API pricing, context window size and other specifications. For more detailed information, visit the GPT-5.1 Thinking or Kimi K2-Thinking-0905 page. See also the complete list of AI model comparisons.