---
title: Imagen 3 Fast | Runware Docs
url: https://runware.ai/docs/models/google-imagen-3-fast
description: High speed Imagen 3 Fast model for rapid image generation
---
# Imagen 3 Fast

Imagen 3 Fast is a streamlined text to image model that targets low latency use cases. It delivers bright images with strong contrast and improved prompt adherence. Ideal for apps that need fast image generation inside Vertex AI and Firebase with stable, predictable performance.

- **ID**: `google:1@2`
- **Status**: live
- **Creator**: Google
- **Release Date**: July 31, 2024
- **Capabilities**: Text to Image

## Pricing

- **1k**: `$0.02`

## Compatibility & Validation

`width` and `height` must be used together.

---

The following dimension combinations are supported:

| Configuration | Dimensions |
| --- | --- |
| `1K (1:1)` | `1024x1024` |
| `1K (9:16)` | `768x1408` |
| `1K (16:9)` | `1408x768` |
| `1K (7:10)` | `896x1280` |
| `1K (10:7)` | `1280x896` |

## Request Parameters

**API Options**

Platform-level options for task execution and delivery.

### [taskType](https://runware.ai/docs/models/google-imagen-3-fast#request-tasktype)

- **Type**: `string`
- **Required**: true
- **Value**: `imageInference`

Identifier for the type of task being performed

### [taskUUID](https://runware.ai/docs/models/google-imagen-3-fast#request-taskuuid)

- **Type**: `string`
- **Required**: true
- **Format**: `UUID v4`

UUID v4 identifier for tracking tasks and matching async responses. Must be unique per task.

### [outputType](https://runware.ai/docs/models/google-imagen-3-fast#request-outputtype)

- **Type**: `string`
- **Default**: `URL`

Image output type.

**Allowed values**: `URL` `base64Data` `dataURI`

### [outputFormat](https://runware.ai/docs/models/google-imagen-3-fast#request-outputformat)

- **Type**: `string`
- **Default**: `JPG`

Specifies the file format of the generated output. The available values depend on the task type and the specific model's capabilities.

- \`JPG\`: Best for photorealistic images with smaller file sizes (no transparency).
- \`PNG\`: Lossless compression, supports high quality and transparency (alpha channel).
- \`WEBP\`: Modern format providing superior compression and transparency support.

> [!NOTE]
> \*\*Transparency\*\*: If you are using features like background removal or LayerDiffuse that require transparency, you must select a format that supports an alpha channel (e.g., \`PNG\`, \`WEBP\`, \`TIFF\`). \`JPG\` does not support transparency.

**Allowed values**: `JPG` `PNG` `WEBP`

### [outputQuality](https://runware.ai/docs/models/google-imagen-3-fast#request-outputquality)

- **Type**: `integer`
- **Min**: `20`
- **Max**: `99`
- **Default**: `95`

Compression quality of the output. Higher values preserve quality but increase file size.

### [webhookURL](https://runware.ai/docs/models/google-imagen-3-fast#request-webhookurl)

- **Type**: `string`
- **Format**: `URI`

Specifies a webhook URL where JSON responses will be sent via HTTP POST when generation tasks complete. For batch requests with multiple results, each completed item triggers a separate webhook call as it becomes available.

**Learn more** (1 resource):

- [Webhooks](https://runware.ai/docs/platform/webhooks) (platform)

### [deliveryMethod](https://runware.ai/docs/models/google-imagen-3-fast#request-deliverymethod)

- **Type**: `string`
- **Default**: `sync`

Determines how the API delivers task results.

**Allowed values**:

- `sync` Returns complete results directly in the API response.
- `async` Returns an immediate acknowledgment with the task UUID. Poll for results using getResponse.

**Learn more** (1 resource):

- [Task Polling](https://runware.ai/docs/platform/task-polling) (platform)

### [uploadEndpoint](https://runware.ai/docs/models/google-imagen-3-fast#request-uploadendpoint)

- **Type**: `string`
- **Format**: `URI`

Specifies a URL where the generated content will be automatically uploaded using the HTTP PUT method. The raw binary data of the media file is sent directly as the request body. For secure uploads to cloud storage, use presigned URLs that include temporary authentication credentials.

**Common use cases:**

- **Cloud storage**: Upload directly to S3 buckets, Google Cloud Storage, or Azure Blob Storage using presigned URLs.
- **CDN integration**: Upload to content delivery networks for immediate distribution.

```text
// S3 presigned URL for secure upload
https://your-bucket.s3.amazonaws.com/generated/content.mp4?X-Amz-Signature=abc123&X-Amz-Expires=3600

// Google Cloud Storage presigned URL
https://storage.googleapis.com/your-bucket/content.jpg?X-Goog-Signature=xyz789

// Custom storage endpoint
https://storage.example.com/uploads/generated-image.jpg
```

The content data will be sent as the request body to the specified URL when generation is complete.

### [safety](https://runware.ai/docs/models/google-imagen-3-fast#request-safety)

- **Path**: `safety.checkContent`
- **Type**: `object (2 properties)`

Content safety checking configuration for image generation.

#### [checkContent](https://runware.ai/docs/models/google-imagen-3-fast#request-safety-checkcontent)

- **Path**: `safety.checkContent`
- **Type**: `boolean`
- **Default**: `false`

Enable or disable content safety checking. When enabled, defaults to `fast` mode.

#### [mode](https://runware.ai/docs/models/google-imagen-3-fast#request-safety-mode)

- **Path**: `safety.mode`
- **Type**: `string`
- **Default**: `none`

Safety checking mode for image generation.

**Allowed values**:

- `none` Disables checking.
- `fast` Performs a single check.

### [ttl](https://runware.ai/docs/models/google-imagen-3-fast#request-ttl)

- **Type**: `integer`
- **Min**: `60`

Time-to-live (TTL) in seconds for generated content. Only applies when `outputType` is `URL`.

### [includeCost](https://runware.ai/docs/models/google-imagen-3-fast#request-includecost)

- **Type**: `boolean`
- **Default**: `false`

Include task cost in the response.

### [numberResults](https://runware.ai/docs/models/google-imagen-3-fast#request-numberresults)

- **Type**: `integer`
- **Min**: `1`
- **Max**: `20`
- **Default**: `1`

Number of results to generate. Each result uses a different seed, producing variations of the same parameters.

**Generation Parameters**

Core parameters for controlling the generated content.

### [model](https://runware.ai/docs/models/google-imagen-3-fast#request-model)

- **Type**: `string`
- **Required**: true
- **Value**: `google:1@2`

Identifier of the model to use for generation.

**Learn more** (3 resources):

- [Text To Image: Model Selection The Foundation Of Generation](https://runware.ai/docs/guides/text-to-image#model-selection-the-foundation-of-generation) (guide)
- [Image Inpainting: Model Specialized Inpainting Models](https://runware.ai/docs/guides/image-inpainting#model-specialized-inpainting-models) (guide)
- [Image Outpainting: Other Critical Parameters](https://runware.ai/docs/guides/image-outpainting#other-critical-parameters) (guide)

### [positivePrompt](https://runware.ai/docs/models/google-imagen-3-fast#request-positiveprompt)

- **Type**: `string`
- **Required**: true
- **Min**: `2`
- **Max**: `3000`

Text prompt describing elements to include in the generated output.

**Learn more** (2 resources):

- [Text To Image: Prompts Guiding The Generation](https://runware.ai/docs/guides/text-to-image#prompts-guiding-the-generation) (guide)
- [Image Outpainting: Other Critical Parameters](https://runware.ai/docs/guides/image-outpainting#other-critical-parameters) (guide)

### [width](https://runware.ai/docs/models/google-imagen-3-fast#request-width)

- **Type**: `integer`
- **Required**: true
- **Paired with**: height

Width of the generated media in pixels.

**Learn more** (2 resources):

- [Image To Image: Dimensions Changing Aspect Ratio](https://runware.ai/docs/guides/image-to-image#dimensions-changing-aspect-ratio) (guide)
- [Image Outpainting: Dimensions Critical For Outpainting](https://runware.ai/docs/guides/image-outpainting#dimensions-critical-for-outpainting) (guide)

### [height](https://runware.ai/docs/models/google-imagen-3-fast#request-height)

- **Type**: `integer`
- **Required**: true
- **Paired with**: width

Height of the generated media in pixels.

**Learn more** (2 resources):

- [Image To Image: Dimensions Changing Aspect Ratio](https://runware.ai/docs/guides/image-to-image#dimensions-changing-aspect-ratio) (guide)
- [Image Outpainting: Dimensions Critical For Outpainting](https://runware.ai/docs/guides/image-outpainting#dimensions-critical-for-outpainting) (guide)

## Response Parameters

### [taskType](https://runware.ai/docs/models/google-imagen-3-fast#response-tasktype)

- **Type**: `string`
- **Required**: true
- **Value**: `imageInference`

Type of the task.

### [taskUUID](https://runware.ai/docs/models/google-imagen-3-fast#response-taskuuid)

- **Type**: `string`
- **Required**: true
- **Format**: `UUID v4`

UUID of the task.

### [imageUUID](https://runware.ai/docs/models/google-imagen-3-fast#response-imageuuid)

- **Type**: `string`
- **Required**: true
- **Format**: `UUID v4`

UUID of the output image.

### [imageURL](https://runware.ai/docs/models/google-imagen-3-fast#response-imageurl)

- **Type**: `string`
- **Format**: `URI`

URL of the output image.

### [imageBase64Data](https://runware.ai/docs/models/google-imagen-3-fast#response-imagebase64data)

- **Type**: `string`

Base64-encoded image data.

### [imageDataURI](https://runware.ai/docs/models/google-imagen-3-fast#response-imagedatauri)

- **Type**: `string`
- **Format**: `URI`

Data URI of the output image.

### [seed](https://runware.ai/docs/models/google-imagen-3-fast#response-seed)

- **Type**: `integer`

The seed used for generation. If none was provided, shows the randomly generated seed.

### [NSFWContent](https://runware.ai/docs/models/google-imagen-3-fast#response-nsfwcontent)

- **Type**: `boolean`

Flag indicating if NSFW content was detected.

### [cost](https://runware.ai/docs/models/google-imagen-3-fast#response-cost)

- **Type**: `float`

Task cost in USD. Present when `includeCost` is set to `true` in the request.

## Examples

### Subterranean Tram Dining Arcade (Text to Image)

![Subterranean Tram Dining Arcade](https://assets.runware.ai/examples/google-imagen-3-fast/bfbbdf1c-b7bd-449c-8c70-79ba70cae065.jpg)

**Request**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "615d94fe-66f7-4089-a4e4-727b67f5b257",
  "model": "google:1@2",
  "positivePrompt": "A vast underground dining arcade built inside a repurposed tram depot, with vintage streetcars converted into tiny restaurants and bakeries, long tiled platforms covered in hanging citrus trees, polished brass signage, checkerboard stone floors, glowing paper menus, families and travelers browsing between stalls, chefs visible through tram windows, stacked pastries, copper cookware, baskets of figs and blood oranges, drifting steam from soup bowls, intricate ceiling beams and skylight shafts filtering dusty golden daylight from grates above, bright saturated colors, strong contrast, crisp architectural detail, lively yet cozy atmosphere, wide cinematic composition, highly readable scene structure, realistic textures, sharp focus",
  "width": 1408,
  "height": 768
}
```

**Response**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "615d94fe-66f7-4089-a4e4-727b67f5b257",
  "imageUUID": "4f1503ed-26c7-4248-a945-1b9fe5f6ebea",
  "imageURL": "https://im.runware.ai/image/os/a22d05/ws/2/ii/4f1503ed-26c7-4248-a945-1b9fe5f6ebea.jpg",
  "seed": 897124337,
  "cost": 0.02
}
```

---

### Lantern Regatta Under Stormclouds (Text to Image)

![Lantern Regatta Under Stormclouds](https://assets.runware.ai/examples/google-imagen-3-fast/cbec94e8-5f1e-4190-bc3a-584ddca51fb7.jpg)

**Request**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "7afc6ac9-e91e-4281-8797-94fd0fd8b31a",
  "model": "google:1@2",
  "positivePrompt": "A wide cinematic scene of a river regatta at twilight, dozens of elaborate handmade lantern boats drifting across dark rippling water, each vessel shaped like mythical birds, koi, and pagoda-inspired sculptures, warm amber and crimson light glowing from within paper and silk panels, low stormclouds rolling overhead, distant willow-lined banks filled with bundled spectators holding parasols, gusts of wind bending reeds near the shoreline, reflections shattered across the water, bright highlights and deep shadows, vivid contrast, crisp detail, atmospheric depth, dynamic composition, richly textured materials, expressive sky, realistic lighting, no text, no watermark",
  "width": 1408,
  "height": 768
}
```

**Response**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "7afc6ac9-e91e-4281-8797-94fd0fd8b31a",
  "imageUUID": "5faf69d5-9ae1-4432-bd6d-7b8de6acdcc8",
  "imageURL": "https://im.runware.ai/image/os/a13d12/ws/2/ii/5faf69d5-9ae1-4432-bd6d-7b8de6acdcc8.jpg",
  "seed": 623756672,
  "cost": 0.02
}
```

---

### Volcanic Glasshouse Orchid Atrium (Text to Image)

![Volcanic Glasshouse Orchid Atrium](https://assets.runware.ai/examples/google-imagen-3-fast/b347f5bb-e273-4cab-9ca1-504e399c704e.jpg)

**Request**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "10edef16-4089-48e5-9c25-a9f9053783e9",
  "model": "google:1@2",
  "positivePrompt": "A sweeping wide view inside a grand glasshouse built within an ancient volcanic cavern, terraced walkways curving around a central orchid atrium, giant translucent petals in crimson, amber, and ivory, polished black basalt floors reflecting warm sunlight pouring through a fractured crystal ceiling, delicate hanging bridges, mist drifting above fern beds, tiny brass irrigation pipes, rare tropical plants thriving against rugged lava walls, a few visitors in understated earth-toned clothing for scale, bright image, strong contrast, highly detailed, crisp focus, imaginative yet believable architecture, cinematic depth, vibrant natural colors",
  "width": 1408,
  "height": 768
}
```

**Response**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "10edef16-4089-48e5-9c25-a9f9053783e9",
  "imageUUID": "728c0495-75e0-4645-a38d-321ddbb3ea7d",
  "imageURL": "https://im.runware.ai/image/os/a07d11/ws/2/ii/728c0495-75e0-4645-a38d-321ddbb3ea7d.jpg",
  "seed": 896861164,
  "cost": 0.02
}
```

---

### Wind-Carved Ice Caravan (Text to Image)

![Wind-Carved Ice Caravan](https://assets.runware.ai/examples/google-imagen-3-fast/97a63866-6f25-40b0-a272-18e867072b96.jpg)

**Request**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "7e10e98a-8179-4c4c-88e5-d259ed9caa6e",
  "model": "google:1@2",
  "positivePrompt": "A wide cinematic scene of a caravan crossing a frozen tidal plain at sunrise: towering shaggy pack animals draped in embroidered blankets pull sledges loaded with crystal crates and brass instruments, while bundled travelers in fur-lined coats guide them between jagged blue ice ridges. In the distance, enormous wind-carved arches of translucent ice rise from the snow, with flocks of white birds circling overhead. The sky glows in bands of apricot, pale gold, and cold turquoise, reflecting across polished ice and shallow meltwater. Crisp footprints, drifting snow, visible breath, frosted ropes, sparkling surface textures, bright highlights, deep cool shadows, vivid contrast, sharp focus, richly detailed environmental storytelling, adventurous mood, painterly realism.",
  "width": 1408,
  "height": 768
}
```

**Response**:

```json
{
  "taskType": "imageInference",
  "taskUUID": "7e10e98a-8179-4c4c-88e5-d259ed9caa6e",
  "imageUUID": "a9b274dc-c598-4afc-999b-7eb7eb473493",
  "imageURL": "https://im.runware.ai/image/os/a14d18/ws/2/ii/a9b274dc-c598-4afc-999b-7eb7eb473493.jpg",
  "seed": 942498114,
  "cost": 0.02
}
```