As Adobe Acrobat, pdfToolbox uses the term "Layers" to refer to what is technically called "Optional Content Groups" in the PDF specification. The rest of this article will use the term layers. The Layer Explorer lets you create and manage layers as well as explore layers already present in the PDF document.

1. The "Layer views" section allows you to define and manage different layer views. A layer view determines the visibility of layers, allowing you to create predefined sets of layer visibilities.
2. The "Settings menu" provides options to create, edit, delete, and save layer views. To add a new layer view:
   1. Adjust the visibility of layers in the Layers List (3).
   2. Click the + button to save the current visibility settings as a new predefined view.
3. The lower section of the Layer Explorer  displays all layers present in the current document. These layers correspond to Optional Content Groups (OCG) in PDF syntax. You can toggle their visibility by clicking the eye icon next to each layer's name.
   • Use the following shortcut to toggle layer visibility: Alt (Win) / Option (macOS) + click on the eye icon → Hides all layers except the selected one.
   • If Processing Steps information is available for a layer, it will be listed after the name of the layer. More details can be found in the article: Working with processing steps metadata for a layer.
4. The "Actions menu" allows you to:
   • Create, rename, and delete layers.
   • Use the "Add missing layer" Action (introduced in pdfToolbox 16) to assign objects without a layer to a new or existing layer.
5. The "Save Visibility" option allows you to set specific layers as initially invisible. To modify initial visibility:
   1. Turn off the layers that should be invisible.
   2. Click the "Save Visibility" button at the bottom of the Layer Explorer.

If the current PDF file has no layers, the Layer Explorer will display options for creating new layers using pdfToolbox.