Grok 4.20 0309 vs Mercury 2
xAI vs Inception — benchmarks, pricing, and capabilities side by side.
- •Grok 4.20 0309 has the higher intelligence index (88.5 vs 77)
- •Mercury 2 is cheaper ($0.25 vs $2.00 per 1M input)
- •Mercury 2 is faster
| Grok 4.20 0309 | Mercury 2 | |
|---|---|---|
| Intelligence index | 88.5 | 77 |
| Developer | xAI | Inception |
| Type | LLM | LLM |
| Access | — | API only |
| Context window | — | 128,000 tokens |
| Input price | $2.00 / 1M | $0.25 / 1M |
| Output price | $6.00 / 1M | $0.75 / 1M |
| Speed | 97 tok/s | 790 tok/s |
| Released | March 10, 2026 | March 4, 2026 |
| Parameters | — | — |
| Input modalities | — | Text |
| Output modalities | — | Text |
Shared benchmarks
Grok 4.20 0309
Mercury 2
GPQA Diamond
88.5
77
Humanity’s Last Exam
30
15.5