xAI: Grok 4 Fastx-ai
Bottom Line
xAI: Grok 4 Fast: $0.20/1M input, $0.50/1M output, 2.0M context, CPS grade B. Grok 4 Fast is xAI's latest multimodal model with SOTA cost-efficiency and a 2M token context window. It comes in two flavors: non-reasoning and reasoning. Read more about the model...
API Pricing (per 1M tokens)
| Input | $0.20 |
| Output | $0.50 |
| Cache Read | — |
| Cache Write | — |
| Blended (3:1) | $0.28 |
Specs & Performance
| Context Length | 2.0M |
| Max Output | 30K |
| Intelligence | 11 |
| Coding | 19 |
| Math | 41 |
| Speed | — |
| TTFT | — |
| CPS Grade | B |
| Input / Output Modalities | text, image, file → text |
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FAQ
How much does the xAI: Grok 4 Fast API cost?
xAI: Grok 4 Fast costs $0.20/1M input tokens and $0.50/1M output tokens. Blended cost at a 3:1 ratio is about $0.28/1M tokens.
What is the context window of xAI: Grok 4 Fast?
xAI: Grok 4 Fast supports a 2.0M token context window with up to 30K output tokens.
Is xAI: Grok 4 Fast worth it?
xAI: Grok 4 Fast has a CPS grade of B (score 59), intelligence index 11, coding index 19. Use the compare page to benchmark against rivals.