GPT-5.3-Codex vs Kimi K2.5
OpenAI vs Moonshot AI — benchmarks, pricing, and capabilities side by side.
- •GPT-5.3-Codex has the higher intelligence index (91.5 vs 87.9)
- •Kimi K2.5 is cheaper ($0.40 vs $1.75 per 1M input)
- •GPT-5.3-Codex is faster
- •GPT-5.3-Codex has a larger context window (400K)
| GPT-5.3-Codex | Kimi K2.5 | |
|---|---|---|
| Intelligence index | 91.5 | 87.9 |
| Developer | OpenAI | Moonshot AI |
| Type | Multimodal | Multimodal |
| Access | API only | Open weights |
| Context window | 400,000 tokens | 262,144 tokens |
| Input price | $1.75 / 1M | $0.40 / 1M |
| Output price | $14.00 / 1M | $1.90 / 1M |
| Speed | 73 tok/s | 35 tok/s |
| Released | February 24, 2026 | January 27, 2026 |
| Parameters | — | 1T (32B active) |
| Input modalities | Text, Image | Text, Image |
| Output modalities | Text | Text |
Shared benchmarks
GPT-5.3-Codex
Kimi K2.5
GPQA Diamond
91.5
87.9
Humanity’s Last Exam
39.9
29.4