Introduction
Expand Image extends the canvas of any image to a new aspect ratio, filling in the expanded areas to match the original scene. Select your target aspect ratio and optionally describe what should appear in the new space— Expand Image handles the rest.
It's useful for designers, social media managers, content teams, or anyone who needs to reformat an image for a different platform or layout without cropping or losing the original composition.
Prerequisites
Before using Expand Image, you'll need:
- An input image — any photo, image, or illustration you want to expand to a new aspect ratio
This app requires credits to run and does not support infinite generations in Explore Mode.
Step 1 — Accessing Expand Image
Expand Image lives in the Apps section of Runway. You can get there two ways:
- Navigate to Apps in the left sidebar, then search to find Expand Image
- Navigate to Apps in the left sidebar, select the Image category, and locate Expand Image
Select the app to open it.
Step 2 — Adding the inputs
Expand Image has one required image input, a required aspect ratio selection, and an optional directions field.
Input Image
Upload the image you want to expand by using the Select button, drag and drop it into the upload area, or select Brand to pull from your Brand Kit assets when configured on Enterprise accounts.
Aspect Ratio
Select the target aspect ratio you want to expand your image to. Available options are:
- 16:9
- 9:16
- 1:1
- 4:3
- 3:4
- 21:9
The app will extend the canvas to fit the selected ratio, generating new content in the expanded areas.
Add directions (Optional)
Use the directions field to describe what should appear in the expanded areas of the image. This field is optional— Expand Image will intelligently fill the new space based on the existing image content, so you only need to add directions if you want to guide what appears there specifically.
Step 3 — Generating with Expand Image
Before generating, confirm:
- Your input image has been uploaded
- Your target aspect ratio has been selected
Once everything looks good, select Generate. Expand Image runs on Nano Banana Pro or Nano Banana, which can be chosen through the model selector in the bottom left-hand corner.
Example outputs
| Input Image | Target Ratio | Directions | Output |
|---|---|---|---|
16:9 |
(none) | ||
9:16 |
Add fizz bubbles around the edges | ||
21:9 |
Extend to show the mountain range on both sides |
Next steps
You've used Expand Image to reformat an image to a new aspect ratio without cropping. From here, you might explore:
- Multi-Shot Video — Transform your resized image into a video with multiple shots.
- Upscale Image — Upscale the image into 4K quality with the click of a button.