How to see and hide the layers in a PDF

You see a PDF's layers in PDF by Zaweba by choosing View > Layers. The list shows every layer in the document, and you can show or hide each one, narrow the list to the layers used on the page you're looking at, and press Reset to put everything back to how the document was set to open.

Layers are groups of content that can be switched on and off, a bit like transparent sheets laid over each other. They turn up most in technical drawings, maps and plans exported from design programs, and sometimes in forms or brochures that hold a version in each language on separate layers.

Why you would use them

A building plan might keep walls, electrics, plumbing and dimensions on separate layers. Hiding everything except the electrics makes the circuit easy to follow. A map might hold roads, contours and labels apart, so you can strip it back to just the information you need.

In a document with several languages on layers, showing only your language turns a cluttered page into a clean one. And when a page looks oddly busy, opening the layers list often explains why: several sets of content are switched on together.

Showing and hiding layers

Open the document and choose View > Layers. If the PDF has layers, they appear in a list. If the list is empty, the file has none, and everything you see is just ordinary page content.

Click a layer to show or hide it. The page redraws as you go, so you can see straight away what each layer holds. Turning layers off one at a time is a good way to learn how an unfamiliar drawing is put together.

On a long document, use the option to show only this page's layers. A set of drawings may have dozens of layers across all its sheets, and narrowing the list to the page in view keeps it manageable.

When you've finished exploring, press Reset. That puts back the default state, which is how the document's author meant it to be seen.

What hiding does and doesn't do

Hiding a layer changes the view, not the content. The hidden information is still in the file, so hiding a layer is not a way to remove something before sharing. For that, use the app's redaction tools, which take content out properly.

Be careful when printing. What you see is a useful guide to what you get, but check the preview in the Print window before printing a drawing with layers switched off, so you know exactly what is going on paper.

Use Reset before passing a file on if you've been experimenting, so the next person sees it as intended.

Other viewing tools that help with drawings

Layers pair well with the app's other tools for technical documents. View > Rulers and grid puts millimetre rulers and a grid on the view, with guides you can drag out from the rulers, which helps when you're checking alignment. Zooming in and the page layout choices let you see a whole sheet or the fine detail.

PDF by Zaweba opens large files quickly and works offline, so a big set of drawings is quick to open and explore without uploading it anywhere. For anyone who receives plans or maps as PDFs, the layers list is one of the first places to look.