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xAI / x-ai/grok-4-fast
xAI: Grok 4 Fast
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...
2,000,000
Context
30,000
Max output
$0.20 / 1M
Prompt price
2025-09-19
Created
01 / Snapshot
Pricing, context, modalities, and parameters.
Model Radar detail pages stay neutral and operator-readable: core metadata first, then workflow fit.
| Provider | xAI | Input modalities | text, image, file |
|---|---|---|---|
| Output modalities | text | Prompt price | $0.20 / 1M |
| Completion price | $0.50 / 1M | Request price | N/A |
| Context length | 2,000,000 | Max completion tokens | 30,000 |
| Supported parameters | include_reasoning, logprobs, max_tokens, reasoning, response_format, seed, structured_outputs, temperature, tool_choice, tools, top_logprobs, top_p | ||
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x-ai/grok-4-fast
xAI: Grok 4 Fast
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...
Deep analysis
Cross-modal work
Long context
High-volume usage
vision
tool-capable
long-context
low-cost
03 / Colophon
Routes and exits.
Each model page stays simple: overview, compare, related models, then back to the public hub.