# How to use layer masks in Photoshop on Mac: step by step for beginners

> Learn how to use layer masks in Photoshop on Mac. Add a mask, paint black to hide and white to reveal, then fix the usual problems.

URL: https://www.lazur.app/how-to/use-layer-masks-in-photoshop
Updated: 2026-11-08

To use a layer mask in Photoshop on Mac, select the layer, click Add Layer Mask at the bottom of the Layers panel, then paint black to hide and white to reveal. Option-click that button instead to start with a black mask that hides the whole layer.

## Quick answer

- Select the layer in the Layers panel, then click Add Layer Mask at the bottom of the panel.
- A plain click adds a white mask that shows everything. Option-click adds a black mask that hides everything.
- Paint black to hide and white to reveal. Press X to swap colors when the wrong one is on top.
- Click the mask thumbnail before you paint. If nothing changes, check which thumbnail is selected.
- Keep a PSD copy of your file so the mask stays editable.

Applies to: Photoshop desktop app on macOS, 27.x release line. Time: 15 min. Difficulty: Easy.

## What you need

- Photoshop desktop app installed on your Mac
- An open file with at least one layer
- A Mac keyboard with Option and Command keys

## How to Add and edit a layer mask in Photoshop on Mac in Photoshop on a Mac

1. **Open the file and show the Layers panel.** (Window > Layers) Open your file in Photoshop. If the Layers panel is hidden, go to Window > Layers. Each row in the panel is one layer, and the top row sits in front of the rest. Tip: The Layers panel shows the thumbnails. The Properties panel does not.
2. **Select the layer you want to mask.** Click the layer name once in the Layers panel. The row highlights. The mask attaches to the highlighted layer, so check the name before the next step. Tip: Double-click a name to rename the layer. Clear names save time later.
3. **Click Add Layer Mask.** (Layer > Layer Mask > Reveal All) Look at the bottom of the Layers panel. Click the Add Layer Mask button, which is a circle inside a rectangle. A white thumbnail appears next to the layer thumbnail. Tip: Nothing looks different yet. A white mask reveals the whole layer.
4. **Option-click for a black mask instead.** (Layer > Layer Mask > Hide All) Shortcut: ⌥ click. Hold Option and click the same button to add a black mask. The mask hides the whole layer, so the layer disappears from the canvas until you paint on the mask. Tip: Use this when you want to paint the layer in, not cut it out.
5. **Click the mask thumbnail before you paint.** Shortcut: B and X. Click the mask thumbnail so it is the active target. Press B for the Brush Tool. Press X to swap the foreground and background colors until the color you need is on top. Tip: Black paint hides, white paint reveals, and gray paint fades.
6. **Paint black to hide and white to reveal.** Paint on the canvas with the mask targeted. Black strokes hide the layer and show the layers below. White strokes bring the layer back. Lower the brush opacity for a gentle fade. Tip: A soft-edged brush blends better than a hard one, especially around hair.
7. **Check the mask on its own.** Shortcut: ⌥ click thumbnail. Option-click the mask thumbnail to view the mask on the canvas. Option-click the thumbnail again to return to normal view. White areas are visible and black areas are hidden. Tip: Tap the backslash key to show an overlay of the mask.
8. **Turn the mask off to compare.** Shortcut: ⇧ click thumbnail. Shift-click the mask thumbnail to disable it. A red X appears on the thumbnail, and the full layer returns. Shift-click again to turn the mask back on. Tip: A disabled mask makes it look like the mask does nothing. Check for the red X first.
9. **Save as a PSD to keep the mask editable.** (File > Save As) Choose File > Save As and pick Photoshop as the format. A PSD keeps the layers and masks. Flattening or exporting to JPEG removes them. Tip: Keep the PSD as your master file and export copies for sharing.

![Designer at a Mac laptop in a studio learning how to use layer masks in Photoshop](https://images.lazur.app/content-images/howto/use-layer-masks-in-photoshop/how-to-use-layer-masks-in-photoshop-1-4698d5.jpg)

## What a layer mask does in Photoshop

A layer mask controls which part of a layer you can see. It does not delete pixels. The layer stays whole, and the mask decides what shows through. That matters because you can change your mind later. Paint the mask back and the hidden part returns.

The mask works in shades of gray. White reveals the layer. Black hides it. Gray hides part of the layer, so the layers below show through a little. The Layers panel shows the mask as a second thumbnail beside the layer thumbnail. Click that thumbnail when you want to work on the mask.

## Before you start: check the layer and the version

Two things trip people up before they paint anything. The first is the Background layer. The bottom layer in a new or imported file is often named Background, and it is locked. A locked Background layer does not take a mask as it is. Double-click it to turn it into a normal layer. I could not check this in Adobe's own help pages, because they did not load during my research.

The second is the version. The steps on this page match the desktop app as far as the sources I could read. The latest desktop release I could confirm is Photoshop 27.11, dated 2026-09-01. That date is older than today, so a newer build may exist. Check your version under Photoshop > About Photoshop. The 27.10 and 27.11 release notes list no changes to layer masks.

If you are not sure which build you have, read [how to check your Photoshop version on Mac](https://www.lazur.app/how-to/check-your-photoshop-version-in-photoshop) first. It takes a minute and saves confusion when a menu looks different from the one in this guide.

## How to add a layer mask in Photoshop on Mac

The core workflow fits in a few clicks. You select a layer, add a mask to it, and paint on the mask. Each stroke changes what the layer shows. You never touch the layer pixels, so the change is easy to reverse.

Watch the thumbnails while you work. The layer thumbnail shows the image. The mask thumbnail shows the black and white pattern. A highlighted border tells you which one your next click or brush stroke affects.

## White reveals, black hides: a hide-all mask in practice

A plain click on Add Layer Mask gives you a white mask. White reveals everything, so nothing looks different yet. Option-click the same button and you get a black mask. Black hides the whole layer, so you start with an empty window and paint in the parts you want.

Say you want a texture to show only on a model's face. Place the texture layer above the photo. Option-click Add Layer Mask. Press B for the Brush Tool, then press X if white is not the foreground color. Paint over the face. The texture appears only where you paint.

![Photo editor at a desk adjusting layers on a computer screen in Photoshop](https://images.lazur.app/content-images/howto/use-layer-masks-in-photoshop/how-to-use-layer-masks-in-photoshop-2-d73012.jpg)

## Make a layer mask from a selection with Select > Subject

When the subject is easy to separate from the background, let Photoshop build the mask. Adobe's tutorial on masks from a selection uses this path. The result is white where the subject was selected and black everywhere else.

1. Select the layer in the Layers panel.
2. Choose Select > Subject.
3. Click Add Layer Mask at the bottom of the Layers panel.
4. Check the mask thumbnail. White should cover the subject.
5. Option-click the mask thumbnail to see it on the canvas, then refine it with the brush.

Subject selection rarely comes out clean on the first try. Hair and fine edges usually need cleanup. Paint black on the mask to remove unwanted areas. Paint white to bring back parts that went missing. A soft brush works best around hair.

## Layer mask keyboard shortcuts on Mac

Julieanne Kost published a list of layer mask shortcuts in 2017. It still covers the core moves. Her post was written for Photoshop CC, and it predates the 27.x version numbers, so test each shortcut once on your own copy. The table below uses Mac keys only.

| Action | Mac keys | What it does |
| --- | --- | --- |
| Invert the mask | ⌘I | Swaps black and white on the mask |
| Target the mask | ⌘\ | Next paint goes onto the mask |
| Target the layer | ⌘2 | Next paint goes onto the layer pixels |
| Show the mask on canvas | ⌥ click thumbnail | Click again to return to normal view |
| Show the overlay | \ (backslash) | Shows the mask as an overlay |
| Turn the mask on or off | ⇧ click thumbnail | A red X means the mask is off |
| Mask to selection | ⌘ click thumbnail | Loads the mask as an active selection |
| Duplicate the mask | ⌥ drag thumbnail | Copies the mask to another layer |

_Mac layer mask shortcuts from Julieanne Kost's 2017 list_

Photoshop has no default Mac shortcut for a basic add-mask action, according to the same post. You can set a custom one in Edit > Keyboard Shortcuts. Option-clicking the Add Layer Mask button remains the fastest route to a hide-all mask.

Mac users often mix up ⌘2 and ⌘\. The first targets the layer. The second targets the mask. If a brush paints something unexpected, look at the Layers panel first. The highlighted thumbnail decides where paint goes.

## Fill a mask or fade it with a gradient

You can fill a whole mask at once. Click the mask thumbnail, then choose Edit > Fill. Under Contents, pick Black, White, or 50% Gray. Black hides, white reveals, and 50% Gray makes the layer half see-through.

For a soft fade, select the mask and press G for the Gradient Tool. Drag from the part you want to hide toward the part you want to show. Watch the mask thumbnail while you drag, so you can redo the drag if the fade lands in the wrong place.

## Worked example: blend a sky into a mountain photo

Here is a realistic case. You have a sky photo sitting on top of a mountain photo. The sky covers everything, and you want the mountain ridge to show through near the bottom of the frame.

1. Place the sky layer above the mountain layer in the Layers panel.
2. Select the sky layer and click Add Layer Mask.
3. Press G for the Gradient Tool and set the gradient from white to black.
4. Drag from the top of the frame down to the ridge line.
5. Check the mask thumbnail. It should run from white at the top to black near the ridge.

Tune the result by painting. If the sky edge looks too hard, paint along it with a soft brush at lower opacity. Keep the mask and the layer separate. You can change the mask later without touching either photo.

![Graphic designer reviewing a masked photo edit on a desktop Mac](https://images.lazur.app/content-images/howto/use-layer-masks-in-photoshop/how-to-use-layer-masks-in-photoshop-3-7d94d1.jpg)

## Layer mask mistakes that waste time

- Painting on the layer instead of the mask. Click the mask thumbnail first, then paint.
- Shift-clicking the thumbnail and forgetting it is off. A red X on the thumbnail means the mask is disabled.
- Mixing up black and white. Black hides and white reveals. Check the thumbnail before you assume the mask is wrong.
- Flattening the file too early. Flattening or exporting to JPEG removes the layers and masks.
- Using a hard brush on hair or fur. Soft edges look more natural.

Most of these come down to one question: which thumbnail is selected? Before you change anything else, look at the Layers panel. The highlighted thumbnail shows where the next click or stroke will land.

## Photoshop on the web or the desktop app

Adobe's Learn tutorial on masks from a selection says it covers Photoshop on the web. Its menus follow the desktop app, though, and the page does not say clearly which app it describes. It also links to version 23.1, which does not match the 27.x numbers in the release notes.

For that reason, this page covers the desktop app on Mac only. If you use the web version, check that app's own help for its menu names before you follow the paths above.

## Keep the layer mask editable

A mask only helps if you keep it. Save your working file as a PSD so the layers and masks stay editable. Export a JPEG or PNG only when the work is finished. If you need a flat image for sharing, keep the PSD as your master copy.

Masks are also the base for cutouts. If your goal is to separate a subject from its background, read [how to remove a background in Photoshop on Mac](https://www.lazur.app/how-to/remove-a-background-in-photoshop). It uses the same mask ideas on a larger scale.

## What to learn next in Photoshop on Mac

Once masks feel natural, try [how to crop an image in Photoshop on Mac](https://www.lazur.app/how-to/crop-an-image-in-photoshop) or [how to add text in Photoshop on Mac](https://www.lazur.app/how-to/add-text-in-photoshop). Each page covers one task from start to finish, with the menu paths for the same desktop app.

## Shortcuts

- Add a hide-all (black) mask: ⌥ click mask button
- Show the mask on canvas: ⌥ click thumbnail
- Disable or enable the mask: ⇧ click thumbnail
- Invert the mask: ⌘I
- Target the mask: ⌘\
- Target the layer: ⌘2
- Load the mask as a selection: ⌘ click thumbnail
- Duplicate the mask to another layer: ⌥ drag thumbnail
- Choose the Brush Tool: B
- Swap foreground and background colors: X

## If it does not work

- **Add Layer Mask is greyed out** Look for a Background layer with a lock icon in the Layers panel. Double-click it to convert it to a normal layer, then add the mask. I could not confirm this in Adobe's help pages, so check their documentation if your file behaves differently.
- **Painting does nothing to the layer** You are probably painting on the mask, or the wrong thumbnail is active. Press ⌘2 to target the layer, or ⌘\ to target the mask, then paint again.
- **The layer disappeared after I added a mask** You probably added a black mask with Option-click, which hides the whole layer. Paint white over the area you want, or select the mask and use Edit > Fill with White.
- **The layer ignores my mask edits** Look for a red X on the mask thumbnail. Shift-click the thumbnail to turn the mask back on.
- **The mask edge looks hard or cut out** Switch to a soft-edged brush and paint with lower opacity along the edge. Option-click the thumbnail to check the mask shape before you decide.
- **The mask is gone after I flattened or exported** Flattening and JPEG or PNG exports remove layers and masks. Undo with ⌘Z if you have not closed the file, or reopen the PSD master copy if you saved one.

## With Lazur

Lazur is a voice assistant for the Mac that lives in the notch. Hold ⌥ ⌘ and ask; it sees your screen, answers out loud, points at buttons and walks you through apps. Hold fn to dictate. Free for 3 days, then $18/month: https://www.lazur.app/download

- “Where is the Add Layer Mask button?”: Lazur circles the Add Layer Mask button at the bottom of the Layers panel and labels it on your screen. You still click it yourself. (Points at it)

## FAQ

### Is a layer mask the same as an eraser?

No. An eraser deletes pixels from the layer. A layer mask hides pixels and keeps them. You can paint the mask white again at any time to bring the hidden part back.

### Why is my Add Layer Mask button greyed out?

The most common cause is a locked Background layer. Double-click the Background layer to turn it into a normal layer, then add the mask. I could not confirm this in Adobe's own help pages, so check their documentation if it does not match your file.

### What is the shortcut to add a layer mask on Mac?

Julieanne Kost's list says Photoshop has no default Mac shortcut for a basic add-mask action. You can set a custom one in Edit > Keyboard Shortcuts. Option-clicking the Add Layer Mask button gives you a hide-all mask.

### Are the basics of layer masks different in older versions?

Photoshop Essentials says the basics have not changed since Photoshop 3.0. It says readers on Photoshop CS5 or earlier should use an older tutorial for the interface.

### Which Photoshop version do I need for this page?

The latest desktop release I could confirm is 27.11, dated 2026-09-01. The August 2026 LTS update sets the Photoshop 2026 LTS version to 26.11.7. A newer build may exist, so check your version under Photoshop > About Photoshop.

### Can I undo a mask edit?

Yes. Press ⌘Z to undo the last step, or use Edit > Undo. Because the mask is separate from the layer, you can also repaint the mask at any time.

### Does Photoshop on the web work the same way?

I could not confirm that. The Adobe Learn page on masks from a selection does not make clear which app it describes. Use this page for the desktop app, and check the web app's help for its menus.

## Sources

1. [Adobe Learn: How to make a layer mask from a selection (Photoshop)](https://www.adobe.com/africa/learn/photoshop/web/make-selection-layer-mask), Adobe, checked 2026-11-09
2. [Julieanne Kost's Blog: Tips for Working with Layer Masks in Photoshop](https://jkost.com/blog/2017/08/15-shortcuts-for-working-with-layer-masks-in-photoshop-cc.html), Julieanne Kost, checked 2026-11-09
3. [Photoshop Essentials: Photoshop Layer Mask Basics For Beginners](https://www.photoshopessentials.com/basics/understanding-photoshop-layer-masks/), Photoshop Essentials, checked 2026-11-09
4. [WhatsNew.fyi: Adobe Photoshop changelog](https://whatsnew.fyi/product/adobe-photoshop), WhatsNew.fyi, checked 2026-11-09