Grok 4.20 0309 vs Step 3.5 Flash
xAI vs StepFun — benchmarks, pricing, and capabilities side by side.
- •Grok 4.20 0309 has the higher intelligence index (88.5 vs 83.1)
- •Step 3.5 Flash is cheaper ($0.09 vs $2.00 per 1M input)
- •Step 3.5 Flash is faster
| Grok 4.20 0309 | Step 3.5 Flash | |
|---|---|---|
| Intelligence index | 88.5 | 83.1 |
| Developer | xAI | StepFun |
| Type | LLM | LLM |
| Access | — | Open weights |
| Context window | — | 262,144 tokens |
| Input price | $2.00 / 1M | $0.09 / 1M |
| Output price | $6.00 / 1M | $0.30 / 1M |
| Speed | 97 tok/s | 194 tok/s |
| Released | March 10, 2026 | January 29, 2026 |
| Parameters | — | — |
| Input modalities | — | Text |
| Output modalities | — | Text |
Shared benchmarks
Grok 4.20 0309
Step 3.5 Flash
GPQA Diamond
88.5
83.1
Humanity’s Last Exam
30
19.1