# PDF layers

The **Layers** view of the sidebar lists a PDF's layers (optional content groups) and lets you show or hide each one. Use it for CAD drawings, maps and documents that put alternatives, translations or answers on separate layers.

**Available in [pre-release 3.7](https://www.sumatrapdfreader.org/prerelease)**

**Open it with `Ctrl + K`, then `Toggle Layers`.** At a glance:

- **Show / hide the view:** `Ctrl + K`, `Toggle Layers`, or the Layers icon in the top sidebar panel's header.
- **Show or hide a layer:** click its row, or select it and press `Space`.
- **Remembered:** the layers you changed stay that way the next time you open the document.

The view and the command are only there for a PDF that has layers.

## Show the Layers view

- `Ctrl + K`, then `Toggle Layers` in the [Command Palette](Command-Palette.md). The command is `CmdToggleLayers`. Bind a shortcut to it as in [Customize keyboard shortcuts](Customize-keyboard-shortcuts.md).
- In the top sidebar panel's header, click the Layers icon (a stack of sheets). The Bookmarks, Thumbnails and Favorites icons switch back.

Note: in SumatraPDF ng the Layers icon is an eye.

The Layers view belongs to the document, so it shows in the top panel. See [Sidebar panels](Thumbnails-sidebar.md#sidebar-panels).

## Show or hide a layer

Each row is a layer, with a check box that is on while the layer is shown.

- Click the row.
- Or move to it with `Up` / `Down` and press `Space`.

The pages and their thumbnails are redrawn without (or with) what is on that layer.

The PDF decides how the list looks:

- **Groups:** a name without a check box is a label for the layers indented under it.
- **Radio buttons:** layers with a round button are alternatives. Showing one hides the others in its group.
- **Locked layers:** a dimmed row can't be changed.

A PDF that doesn't list its layers for the user shows all of them, in a flat list.

## Print with layers

Printing prints the layers that are shown. A layer the PDF marks as print-only (or never printed) follows what the PDF says, as in Acrobat.

## Tips

- Use the Layers view to hide dimensions, annotations or a background layer in a CAD drawing. See [CAD / Engineering Drawings](CAD-Engineering-Drawings.md).
- Showing or hiding a layer doesn't modify the file. To get the layers back as the PDF has them, undo your changes in the view.
- Bind `CmdToggleLayers` to a key if you switch layers often.

## Settings

The layers you changed are saved for each document in its `FileStates` entry as `LayerStates`: `1` (shown) or `0` (hidden) for each layer. It is empty while the layers are as the PDF has them. See [Advanced options settings](Advanced-options-settings.md).

## See also

- [Thumbnails sidebar](Thumbnails-sidebar.md): the sidebar's panels and views
- [CAD / Engineering Drawings](CAD-Engineering-Drawings.md): drawings, which often have layers
- [Command Palette](Command-Palette.md): `Toggle Layers`