Grok 4.3 vs Grok 4 Fast
xAI vs xAI — benchmarks, pricing, and capabilities side by side.
- •Grok 4.3 has the higher intelligence index (90.1 vs 78.7)
- •Grok 4 Fast is cheaper ($0.20 vs $1.25 per 1M input)
- •Grok 4 Fast is faster
- •Grok 4 Fast has a larger context window (2M)
| Grok 4.3 | Grok 4 Fast | |
|---|---|---|
| Intelligence index | 90.1 | 78.7 |
| Developer | xAI | xAI |
| Type | LLM | LLM |
| Access | API only | API only |
| Context window | 1,000,000 tokens | 2,000,000 tokens |
| Input price | $1.25 / 1M | $0.20 / 1M |
| Output price | $2.50 / 1M | $0.50 / 1M |
| Speed | 88 tok/s | 90 tok/s |
| Released | May 6, 2026 | September 19, 2025 |
| Parameters | — | — |
| Input modalities | Text, Image | Text, Image |
| Output modalities | Text | Text |
Shared benchmarks
Grok 4.3
Grok 4 Fast
GPQA Diamond
90.1
85.7
Humanity’s Last Exam
35
20