> For the complete documentation index, see [llms.txt](https://docs.realmacsoftware.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.realmacsoftware.com/squash/quick-guide/editor.md).
# Preview
Compare an image with its processed output
The preview fills the middle of the window, between the image list and the settings sidebar. It shows the selected image so you can compare it with its processed output while you change settings. It replaces the separate full-window Editor from earlier builds of Squash 4.
### Showing an image
The preview is always visible. Click an image in the list to show it. Drag the divider between the list and the preview to change how much space each one has; Squash remembers the list's width. As the list gets narrower, its size columns hide so that filenames stay readable.
### Before and after
The preview shows the original image on the left of a divider and the processed result on the right. Drag anywhere on the image to move the divider. Its position is kept when you select another image.
The **Before** and **After** labels above the preview show the file size of each side; while the After side is being processed, its label says so. The **After** side is encoded with your current format and quality settings, so it shows the same compression artefacts as the exported file. It updates as you change the sidebar settings; allow processing to finish before judging the result.
If the After size is larger than the original, try a lower quality, smaller dimensions or another output format. See [Why a file can get bigger](/squash/quick-guide/nodes/format.md#why-a-file-can-get-bigger).
### Zooming and panning
| Action | How |
| ----------------------- | ------------------------------------------------------- |
| Zoom in | **Command-+** (or **Command-=**), or **View → Zoom In** |
| Zoom out | **Command-Minus**, or **View → Zoom Out** |
| Actual size | **Command-0**, or **View → Actual Size** |
| Zoom to fit | **Command-9**, or **View → Zoom to Fit** |
| Zoom around the pointer | Hold **Option** and scroll, or pinch on a trackpad |
| Pan when zoomed in | Scroll, or hold **Space** and drag |
Zoom ranges from 25% to 800%. Zooming out below the fitted size returns to Zoom to Fit. The zoom level carries over when you select another image, so you can compare the same detail across a batch; clearing the list returns to Zoom to Fit.
### Moving through a batch
Click another row in the list, or use the arrow keys or **View → View Previous Image / View Next Image** when an editing field is not focused.
Previewing an image does not save it to your export destination. Use the [Export](/squash/quick-guide/nodes/export.md) controls when you are happy with the result.
Squash 3 reference screenshots
These screenshots show the earlier Squash 3 interface.
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