> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dreep.cloud/llms.txt
> Use this file to discover all available pages before exploring further.

# Delivery URLs

> Transform an asset at delivery time with dreep.url().

Appends transform parameters to an asset's delivery URL. Pure string work — no network
call, no API key — so it's safe in a render path.

```ts theme={null}
dreep.url(asset, { width: 400, height: 400, fit: "cover", format: "webp" });
// …/fetch/2f928a3f-1d2a-4a2b?fit=cover&format=webp&height=400&width=400
```

## Signature

```ts theme={null}
dreep.url(target: Asset | string, transform?: TransformParams): string
```

| Parameter   | Type              | Description                                             |
| :---------- | :---------------- | :------------------------------------------------------ |
| `target`    | `Asset \| string` | **Required.** An asset, or a URL it previously returned |
| `transform` | `TransformParams` | The transform to apply. Omit for the original           |

It never builds a URL from scratch. The delivery host and API version come from server
configuration, so the only correct base is the one the API already returned. If you store
URLs rather than whole assets, pass the string:

```ts theme={null}
dreep.url(storedUrl, { width: 400 });
```

Transforms run on the fly and are cached, so one original serves every size you ask for.

## Parameters

| Parameter              | Applies to          | Description                                                 |
| :--------------------- | :------------------ | :---------------------------------------------------------- |
| `format`               | image, video, audio | Output format. Also drives OCR (`txt`) and video thumbnails |
| `width`, `height`      | image, video        | Target size in pixels, max 4000                             |
| `fit`                  | image, video        | `cover`, `contain`, `fill`, `inside`, `outside`             |
| `quality`              | image, video        | 1–100                                                       |
| `gravity`              | image               | Crop anchor when resizing                                   |
| `crop`                 | image               | Explicit crop, `left,top,width,height`                      |
| `dpr`                  | image               | Device pixel ratio multiplier, max 3                        |
| `rotate`               | image               | `90`, `180` or `270`                                        |
| `blur`                 | image               | Blur sigma                                                  |
| `bg`                   | image               | Hex fill colour without `#`, e.g. `ffffff`                  |
| `radius`               | image               | Corner radius in px, or `max` for a circle                  |
| `trimStart`, `trimEnd` | video               | Trim points in seconds                                      |
| `videoCodec`           | video               | `h264`, `vp8`, `vp9`, `hevc`                                |
| `fps`                  | video               | Output frame rate                                           |
| `preset`               | image, video        | A saved preset key, applied instead of individual fields    |

See [Image Transformations](/transformations/images) and
[Video Transformations](/transformations/videos) for what each does.

## Type safety

Enum-like parameters are typed unions, so a wrong value is a compile error rather than a
silently ignored query parameter:

```ts theme={null}
dreep.url(asset, { fit: "squish" });  // Type error — not a Fit
dreep.url(asset, { rotate: 45 });     // Type error — 90, 180 or 270
```

## Presets

```ts theme={null}
dreep.url(asset, { preset: "thumbnail" });
// …/fetch/2f928a3f-1d2a-4a2b?p=thumbnail
```

The SDK maps `preset` onto the `p` query parameter the API reads. See
[createPreset()](/node-sdk/presets/create-preset).