How to Take a Partial Screenshot on Mac

Why you don’t need a full-screen screenshot

Most of the time, you don’t want a screenshot of your entire screen. You want a specific error message, a single UI element, a chart, or a paragraph of text. Capturing just the area you need means smaller file sizes, no cropping afterward, and screenshots that communicate exactly what you want without the noise of browser tabs, menu bars, and desktop clutter.

macOS gives you multiple ways to capture a partial screenshot — from a quick keyboard shortcut to a resizable selection box with precise pixel controls. This guide covers every method, including the hidden modifier keys that most tutorials skip.

Method 1: Cmd+Shift+4 (the fastest way)

This is the shortcut you’ll use 90% of the time. Press Cmd+Shift+4 and your cursor turns into a crosshair with pixel coordinates displayed next to it.

1. Press Cmd+Shift+4
2. Click and drag to draw a rectangle around the area you want to capture
3. Release the mouse button to take the screenshot

The screenshot saves to your Desktop as a PNG file. A floating thumbnail appears in the bottom-right corner for five seconds — click it to annotate with Markup, or let it disappear to save automatically.

Pixel dimensions while selecting

As you drag, macOS shows the width and height of your selection in pixels next to the crosshair. This is useful when you need a specific size — for example, capturing a 1200×630 region for a social media card or an 800-pixel-wide image for documentation.

Method 2: Cmd+Shift+5 (resizable selection box)

Press Cmd+Shift+5 to open the Screenshot toolbar. Click Capture Selected Portion (the dashed-rectangle icon) to place a resizable selection box on your screen.

1. Press Cmd+Shift+5
2. Click the Capture Selected Portion button in the toolbar
3. Drag the edges or corners of the selection box to resize it
4. Drag the interior of the box to reposition it
5. Click Capture or press Return

The selection box is persistent — macOS remembers the size and position from your last use. The next time you press Cmd+Shift+5, the box appears in the same spot, which is useful when you need to take multiple screenshots of the same area (like capturing a UI before and after a change).

Hidden modifier keys for precise selections

These modifier keys work during the drag phase of Cmd+Shift+4. Most Mac users never discover them, but they transform partial screenshots from approximate to precise:

You can combine modifiers mid-drag. For example, start dragging, hold Space to reposition, release Space, then hold Shift to lock one axis — all in a single smooth motion.

Copy a partial screenshot to clipboard (no file saved)

Add Ctrl to the shortcut to copy the partial screenshot to your clipboard instead of saving it as a file:

• Ctrl+Cmd+Shift+4 — drag to select, copies to clipboard

This is the fastest workflow when you want to paste a screenshot directly into Slack, email, Notion, or a code review without leaving a file on your Desktop. Press Cmd+V in any app to paste.

All the modifier keys (Space, Option, Shift) work the same way in clipboard mode.

Method 3: Terminal screencapture command

The built-in screencapture command supports interactive area selection from the Terminal. This is useful for scripts, automation, and remote sessions:

# Interactive area selection (same as Cmd+Shift+4)
screencapture -i ~/Desktop/partial.png

# Interactive selection, copy to clipboard
screencapture -ic

# Capture a specific rectangle (x,y,width,height)
screencapture -R 100,200,800,600 ~/Desktop/region.png

The -R flag is especially powerful for automation. It captures a precise pixel rectangle without any user interaction, which is useful for scheduled screenshots, visual regression testing, or monitoring dashboards.

Method 4: Preview app

The Preview app has a built-in screenshot tool that defaults to area selection:

1. Open Preview
2. Go to File > Take Screenshot > From Selection
3. Your cursor turns into a crosshair — drag to select the area
4. The screenshot opens in a new Preview window for immediate editing

This method is useful when you want to annotate or crop the screenshot immediately, since it opens directly in Preview’s editor instead of saving to the Desktop.

Pixel-perfect partial screenshots: tips for precise captures

Zoom in before capturing

If you need to capture a tiny UI element precisely, zoom into the area first using Cmd+= in your browser or app. Then take the partial screenshot at the zoomed level. The text and icons will be sharper and easier to read in the final image.

Use the pixel coordinates

When you press Cmd+Shift+4, the crosshair shows your cursor’s x,y position in screen pixels. Before you start dragging, note the coordinates of where you want to start. This helps when you need to capture the same region repeatedly — start at the same coordinates each time.

Capture with consistent padding

For documentation and presentations, add 20–40 pixels of padding around the element you’re capturing. This prevents the subject from touching the edges and makes the screenshot look more intentional. The Option key (resize from center) helps here — center the crosshair on the element and drag outward symmetrically.

Retina resolution

On Retina Macs, partial screenshots are captured at 2x resolution. A 400×300 selection produces an 800×600 pixel image. This means your screenshots are always sharp, but the file size is larger than you might expect. If you need the image at 1x resolution, resize it in Preview (Tools > Adjust Size) or use the sips command:

sips --resampleWidth 400 screenshot.png

Partial screenshot shortcuts at a glance

Partial screenshot not working? Troubleshooting

• Crosshair doesn’t appear — check that screenshot shortcuts are enabled in System Settings > Keyboard > Keyboard Shortcuts > Screenshots
• Shortcut does nothing — another app may have claimed the same keyboard shortcut. Quit apps like CleanShot X, Snagit, or Loom one at a time to find the conflict
• Screenshot saves but is blank or black — some apps with DRM (Netflix, Apple TV+) block screen capture. Try a different capture method or check if the app allows screenshots in its settings
• Selection area is tiny or offset — if you’re using a non-Retina external monitor with a Retina MacBook, the coordinate mapping can be off. Try disconnecting the external display and capturing on the built-in screen
• No floating thumbnail — this is likely disabled. Press Cmd+Shift+5, click Options, and check Show Floating Thumbnail

When to use partial screenshots vs. window screenshots

macOS offers two ways to capture less than the full screen: area selection (Cmd+Shift+4) and window capture (Cmd+Shift+4 then Space). Here’s when each makes sense: