How to Open Files on Mac: Complete Guide for macOS

Opening files on macOS is designed to be intuitive, but understanding the various methods and file association options gives you greater control over your workflow. Whether you're new to Mac or looking to master advanced file handling techniques, this comprehensive guide covers everything from basic double-clicks to managing default applications and troubleshooting problems.

Basic Methods to Open Files

Double-Click to Open

The most common method:

1. Open Finder (click the Finder icon in Dock, or Command + Space and type "Finder")
2. Navigate to the folder containing your file
3. Double-click the file
4. macOS opens it with the default associated application

Control-Click (Right-Click) and Open

1. Control-click the file (or right-click with two-finger trackpad tap)
2. Select Open from the context menu
3. File opens with default application

This method is particularly useful for opening files from unidentified developers, as it bypasses some Gatekeeper restrictions.

Drag and Drop

1. Open the application you want to use
2. Drag the file from Finder
3. Drop it onto the application window or Dock icon
4. File opens in that specific application

Excellent for opening files in non-default applications without changing permanent associations.

Select and Press Command + Down Arrow

1. Click once to select the file in Finder
2. Press Command (⌘) + Down Arrow
3. File opens with default application

Keyboard shortcut alternative to double-clicking.

Press Space for Quick Look

1. Select a file in Finder
2. Press Spacebar
3. Quick Look preview appears (doesn't fully open the file)
4. Press Space again to close

Quick Look allows you to preview documents, images, videos, and more without launching applications. You can even play videos and flip through multi-page PDFs.

Opening Files with Specific Applications

Using "Open With" Menu

To open a file with an application other than the default:

1. Control-click (right-click) the file
2. Select Open With
3. Choose from the list of compatible applications
4. If your desired app isn't listed, select "Other..."

One-Time Application Selection

When selecting "Other..." from the Open With menu:

1. Browse to the application (usually in /Applications)
2. Don't check "Always Open With"
3. Click Open

The file opens in your selected app just this once, leaving the default association unchanged.

Setting a New Default Application

To permanently change which app opens this file type:

Method 1: Via Open With Menu

1. Control-click the file
2. Select Open With
3. Hold Option (⌥) key—"Open With" changes to "Always Open With"
4. Select your desired application

Method 2: Via Get Info Window

1. Select the file
2. Press Command (⌘) + I (or File menu → Get Info)
3. Expand the "Open with:" section
4. Select your preferred application from dropdown
5. Click "Change All..." button
6. Confirm when prompted

Now all files with this extension will open in the selected application by default.

Managing Default Applications

Changing Defaults for All Files of a Type

1. Select any file of the type you want to configure
2. Command (⌘) + I to open Get Info
3. Under "Open with:", select your preferred application
4. Click "Change All..."
5. Click "Continue" in the confirmation dialog

This changes the default application for all files with this extension system-wide.

Reverting to Original Default

If you want to restore macOS's original default application:

1. Get Info on the file (Command + I)
2. Under "Open with:", look for the application macOS originally suggested
3. Select it and click "Change All..."

Common defaults:

• Images: Preview
• PDFs: Preview
• Text files: TextEdit
• Videos: QuickTime Player
• Music: Music app (or iTunes on older macOS versions)

Opening Files from Within Applications

File → Open Menu

1. Launch the application
2. Click File menu → Open (or press Command + O)
3. Browse to file location in the dialog
4. Select file and click Open

Drag Files to Dock Icons

1. Find your file in Finder
2. Drag it to an application icon in the Dock
3. When the icon highlights, release
4. Application launches and opens the file

Opening Recent Files

Most applications maintain a list of recently opened files:

1. Launch the application
2. Click File menu → Open Recent
3. Select file from the list

Common File Types and Applications

Documents

• .pages: Pages (Apple's word processor)
• .docx, .doc: Pages, Microsoft Word, Google Docs (online)
• .numbers: Numbers (Apple's spreadsheet app)
• .xlsx, .xls: Numbers, Microsoft Excel, Google Sheets
• .key: Keynote (Apple's presentation software)
• .pptx, .ppt: Keynote, Microsoft PowerPoint, Google Slides
• .pdf: Preview (built-in), Adobe Acrobat Reader
• .txt: TextEdit, BBEdit, Visual Studio Code

Images

• .jpg, .png, .gif, .bmp: Preview (built-in), Photos, Pixelmator, Affinity Photo
• .psd: Adobe Photoshop, Affinity Photo, Pixelmator Pro
• .ai: Adobe Illustrator, Affinity Designer
• .sketch: Sketch (design tool)
• .svg: Safari, Chrome, Adobe Illustrator, Affinity Designer

Audio

• .mp3, .aac, .m4a: Music app (built-in), VLC, Spotify
• .wav, .flac: Music app, VLC, Audirvāna

Video

• .mov, .mp4: QuickTime Player (built-in), VLC, IINA
• .avi, .mkv, .flv: VLC, IINA (QuickTime doesn't support these natively)

Archives

• .zip: Archive Utility (built-in), The Unarchiver, Keka
• .rar, .7z, .tar.gz: The Unarchiver, Keka, BetterZip

Troubleshooting: File Won't Open

Error: "There is no application set to open the document"

Cause: macOS doesn't have a default application for this file type.

Solution:

1. Click "Choose Application..." in the error dialog
2. Or click "Search App Store" to find compatible apps
3. Browse to an appropriate application
4. You may need to enable "All Applications" at the bottom of the dialog to see all options

Error: "The application cannot be opened"

Cause: Gatekeeper security is blocking an unsigned or unverified application.

Solution:

1. Control-click the file
2. Select Open
3. Click Open again in the confirmation dialog

This bypasses Gatekeeper for this specific file. For applications:

1. System Preferences → Security & Privacy → General tab
2. Look for a message about the blocked app
3. Click "Open Anyway"

Note: Only do this for software you trust. Gatekeeper protects against malware.

Wrong Application Opens

Cause: Incorrect file association.

Solution:

1. Select the file
2. Command (⌘) + I for Get Info
3. Under "Open with:", select the correct application
4. Click "Change All..." to apply to all files of this type

File Opens but Displays Incorrectly

Possible causes:

• File is corrupted
• Wrong application is opening it
• Application needs updating
• File format is too new or uses proprietary features

Solutions:

• Try opening in an alternative application
• Update the application via App Store or developer's website
• Re-download the file (may have been corrupted)
• Check if file was created on Windows and has compatibility issues

Resetting File Associations (Terminal Method)

If file associations are completely broken, you can reset Launch Services database:

1. Open Terminal (Applications → Utilities → Terminal)
2. Type or paste the following command:

/System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Support/lsregister -kill -r -domain local -domain system -domain user

3. Press Enter
4. Restart your Mac
5. Reconfigure file associations as needed

Warning: This resets all file associations system-wide. Use as a last resort.

Opening Files via Terminal (Command Line)

Using the 'open' Command

open filename.pdf

Opens file with default application.

open -a "Adobe Acrobat" filename.pdf

Opens file with specific application.

open -e filename.txt

Opens file in TextEdit.

open -R filename.pdf

Reveals file in Finder (doesn't open it).

Opening Directories

open .

Opens current directory in Finder.

open ~/Documents

Opens Documents folder in Finder.

Opening URLs

open https://www.example.com

Opens URL in default web browser.

Security Considerations

Gatekeeper Protection

macOS Gatekeeper verifies applications before they run:

• App Store apps: Highest trust level
• Identified developers: Apps signed with valid Apple Developer IDs
• Unidentified developers: Blocked by default

Safe File Handling Practices

• Only open files from trusted sources
• Be cautious with .dmg, .pkg, .app, and .zip files from unknown senders
• Use built-in XProtect and Gatekeeper (don't disable unless necessary)
• Keep macOS updated for latest security patches
• Scan suspicious files with antivirus software (Malwarebytes, etc.)

Quarantine Attribute

Files downloaded from the internet receive a quarantine flag. macOS prompts "This file was downloaded from the internet" when opening. This is a security feature—verify the source before proceeding.

To remove quarantine attribute (advanced users only):

xattr -d com.apple.quarantine filename.pdf

Tips and Tricks

Spotlight Search

1. Press Command (⌘) + Space
2. Type filename or content keywords
3. Select file from results
4. Press Enter to open, or Command + Enter to reveal in Finder

Recent Files in Finder

1. Open Finder
2. Click Recents in the sidebar (or File menu → Recents)
3. See all recently opened/modified files
4. Double-click to reopen

Preview Multiple Files

1. Select multiple files in Finder
2. Press Spacebar for Quick Look
3. Use arrow keys to navigate between files
4. Or click thumbnail strip at bottom

Useful Keyboard Shortcuts

• Command + O: Open selected file or folder
• Command + Down Arrow: Open selected item
• Command + Up Arrow: Go to parent folder
• Spacebar: Quick Look preview
• Command + I: Get Info window
• Command + Delete: Move to Trash
• Command + Shift + Delete: Empty Trash

Opening Files from Dock

Right-click an application icon in the Dock:

• Select "Show Recents"
• Click a recent file to open it immediately

Working with iCloud Drive

1. Open Finder
2. Click iCloud Drive in sidebar
3. Files stored in iCloud appear with cloud icons
4. Double-click to download and open (if not already local)
5. Files sync across all your Apple devices

To save files to iCloud Drive:

1. File → Save (Command + S) in any application
2. Select iCloud Drive in the save location dropdown
3. Choose subfolder (Desktop, Documents, or create new)
4. Click Save

Installing Additional Applications

App Store (Recommended)

1. Open App Store from Dock or Applications folder
2. Search for file type or application name
3. Click Get or Price button
4. Enter Apple ID password or use Touch ID/Face ID
5. App installs automatically and appears in Applications folder

Third-Party Downloads

• Download .dmg (disk image) or .pkg (installer package) from developer's website
• Open the downloaded file
• For .dmg: Drag app icon to Applications folder
• For .pkg: Follow installation wizard
• Eject .dmg if applicable

Popular Free Mac Applications

• VLC Media Player: Plays almost any video/audio format
• IINA: Modern, native macOS media player
• The Unarchiver: Opens any archive format (RAR, 7Z, etc.)
• LibreOffice: Free Office suite (Microsoft Office alternative)
• GIMP: Free image editor (Photoshop alternative)
• Visual Studio Code: Code and text editor
• Keka: File compression and extraction

Opening Files on Network Volumes

1. Finder → Go menu → Connect to Server (Command + K)
2. Enter server address: smb://server.local or afp://server.local
3. Click Connect
4. Enter credentials if prompted
5. Network volume mounts and appears in Finder sidebar
6. Open files normally

To favorite a network location:

1. After connecting, drag the mounted volume to Finder sidebar under "Favorites"
2. Or use Finder → Preferences → Sidebar to customize

mastering file opening techniques on macOS enhances your productivity and gives you greater control over your digital workspace. From simple double-clicks to advanced Launch Services management, understanding these methods ensures you can handle any file type efficiently. Remember to keep your software updated, be cautious with files from unknown sources, and leverage macOS's powerful built-in tools like Quick Look and Spotlight for faster workflows.