Quick Look from the keyboard, anywhere on a Mac
· 5 min read
Select a file in Finder and press the space bar. That is Quick Look: a preview of the file without launching the application that made it. Cmd-Y does exactly the same thing, and Option-Space opens the preview full screen. Press Space or Escape again to close it.
That is the whole shortcut. What follows is where it works beyond Finder, what it can change about a file, and what to do when it shows a blank page instead of a preview.
The three keys
Space opens Quick Look on whatever is selected, and closes it again.
Cmd-Y does the same. It matters because Space is a normal character in text fields, so in any context where the selection might be a name being edited, Cmd-Y is the reliable one.
Option-Space opens Quick Look full screen, which on multiple selected items becomes a slideshow with an index sheet button in the toolbar to see them all as a grid.
While Quick Look is open, the arrow keys move to the next and previous file in the folder without closing anything. Select a folder of forty images, press Space once, then hold Right until you find the one you meant. This is the fastest way to look through a folder on a Mac, and it is faster than any application you could open instead.
Select several files first and Quick Look shows only those, with step arrows in its toolbar.
One thing to know if you use a search app with a global hotkey: Option-Space is a popular choice for those, and whichever app claims it wins. Everywhere uses Option-Space to open its search window over whatever you are doing, and inside its results Space and Cmd-Y both open Quick Look on the highlighted file. If you install something that takes Option-Space, full-screen Quick Look in Finder moves to the Quick Look window’s own full-screen button.
What Quick Look can do besides look
The preview window has a toolbar, and it does more than close.
- Open with, on the right, hands the file to its normal application if the preview is not enough.
- Markup, on images and PDFs, gives you the annotation tools: draw, shapes, text, a stored signature, and crop. Click Done and the change is saved into the file.
- Trim, on audio and video, gives you a yellow trim bar. Done then offers to replace the file or save the trimmed version as a new clip.
- Rotate, on images, turns the file itself, not just the view.
- Share passes the file to Mail, Messages, AirDrop and the rest of the share sheet.
Two of those write to your file. Markup and Trim are real edits, so if the original matters, duplicate it first with Cmd-D in Finder.
Quick Look outside Finder
The shortcut follows you around macOS more than most people notice.
Open and Save dialogs. Any file picker in any application: select a file in the list and press Space. This is the fix for the moment you are staring at six similarly named documents in an upload dialog and cannot tell which is which.
Mail. Select an attachment in a message and press Space. You get the preview without saving the file anywhere first.
Time Machine. Browsing backwards through a folder, Space previews the old version, which is how you confirm you are restoring the right one before you restore it.
Messages, Notes and most Apple apps that show file attachments respond to Space the same way.
Search results. In a Finder search window (Cmd-F), the results are ordinary Finder items, so Space works on them. Finder search tips that actually narrow things down covers getting that result list down to a size where previewing each one is realistic.
The Spotlight window is the exception, because it already draws its own preview panel on the right of the results as you arrow through them.
The preview pane is a different thing
Quick Look is a window you open and close. The preview pane is a permanent column on the right of a Finder window, and people mix them up.
Turn it on with Cmd-Shift-P, or View, Show Preview. It shows a thumbnail plus metadata: dimensions, duration, camera, page count, created and modified dates, tags.
Then View, Show Preview Options lets you choose which metadata fields appear for each kind of file, and whether the Markup and Rotate buttons sit at the bottom of the pane. Turning on the fields you care about makes the pane a faster way to check a file than opening Get Info.
Use both: the pane for metadata while you browse, Quick Look for actually reading the thing.
When the preview is a generic icon
If Quick Look shows a large blank document icon with the filename under it, macOS has no preview generator for that file type. Some formats never had one, and that is the end of it.
When a type that used to preview stops, the cache is the usual suspect. In Terminal:
qlmanage -r
qlmanage -r cache
The first reloads the list of preview generators; the second clears the cached thumbnails so they are drawn fresh. Neither touches your files. Log out and back in afterwards if Finder still shows stale thumbnails. Open Terminal at a folder on a Mac covers getting a Terminal window pointed at the right place in the first place.
Applications can also add preview support for their own formats. In System Settings, look for the Extensions list (under General, Login Items and Extensions on recent macOS; under Privacy and Security on Ventura) and open the Quick Look section. Anything listed there can be switched off, which is worth checking if one file type previews slowly or crashes the preview.
Questions
Why does Space rename a file instead of previewing it? Because the filename is in edit mode. Press Escape first, then Space. This is the main reason to learn Cmd-Y instead, which never types a character.
Can Quick Look show a file inside the Photos library? Not directly, because Finder presents the library as a single item rather than a folder. Find the original of a photo inside the Photos library covers getting at the original file, and once you have it in Finder, Space works normally.
Does Quick Look open the file or just read it? It reads it with a preview generator rather than launching the application, which is why it is fast and why it can show a file whose application is not installed. Markup and Trim are the two exceptions that write back.
How do I go from the preview to actually opening the file? Use the “Open with” button at the right of the Quick Look toolbar, which names the application it will use. Or press Escape to close the preview and Cmd-O in Finder with the file still selected.