Compare models
Put up to 4 models beside each other — token prices, context windows, capabilities and provider, from the same catalogue the model pages read.
| Attribute | Grok 4 Fastgrok-4-fast | Gemini 3.1 Flash Lite Image (Google Vertex AI)gemini-3.1-flash-lite-image-vertex |
|---|---|---|
| Pricing | ||
| Input | $0.07 / 1M | — |
| Output | $0.175 / 1M | — |
| Cache Write (5m) | $0.07 / 1M | Not applicable |
| Cache Write (1h) | $0.07 / 1M | Not applicable |
| Cache Read | $0.07 / 1M | Not applicable |
| Web Search | $0 / 1M | — |
| Request | — | $0.0336 / request |
| Billing | — | Pay Per Request |
| Context | ||
| Max context | 2M | N/A |
| Max output | N/A | N/A |
| Capabilities | ||
| Vision | No | Yes |
| Function Calling | Yes | No |
| JSON Mode | Yes | No |
| Streaming | Yes | No |
| Catalogue | ||
| Provider | xAI | |
| Category | chat | image |
| Charge type | Pay As You Go | Pay Per Request |
| Released | — | — |
| Description | ||
| Summary | Grok 4 Fast is SpaceXAI's cost-efficient multimodal model with a massive 2M-token context window. It’s available in both reasoning and non-reasoning modes, allowing developers to toggle deeper thinking when needed. Designed for scalable performance, it balances speed, capability, and price — with reasoning controllable via the reasoning_enabled API parameter. | Gemini 3.1 Flash Lite Image served from Google Vertex AI. Billed per image at US$0.0336. Call it through /v1/chat/completions with stream set to false; the image is returned in the message content as a base64 data URI. Maximum output resolution is 1K. A request for a larger size returns a 1K image with the same aspect ratio at the same price. When a size is reduced, the response carries an X-Image-Resolution-Capped header with the requested and delivered size. |