A JPEG opens on almost everything without you installing a thing. Double-click it and your device's built-in photo viewer handles it. JPG (the same format, just a shorter name) is the most common image type in the world, so Windows, Mac, phones, and web browsers all read it out of the box. Here's where each one opens it, plus what to do on the rare occasion a file won't cooperate.
Opening a JPEG on Windows
Double-click the file. It opens in the Photos app, which comes with Windows.
Want a different app? Right-click the file and choose Open With. From there you can pick Paint, your web browser, or any image editor you've installed. If you always want a certain app to handle JPGs, choose "Choose another app" and check the box to make it the default.
Opening a JPEG on Mac
Double-click the file and it opens in Preview, the image viewer built into every Mac. Preview also lets you rotate, crop, and mark up the image if you need to.
To use something else, right-click (or Control-click) the file and choose Open With. You can drag the JPG onto an app icon in the Dock too, like Photos or a browser.
Opening a JPEG on iPhone and Android
On a phone, JPEGs live in your photo library automatically. Any image you save from a message, a website, or a download lands in the Photos app on iPhone or the Gallery (or Google Photos) app on Android. Tap it and it opens.
If you download a JPG from an email or the web, it usually goes to your Downloads or a Files app. Tap it there and it opens in the built-in viewer just the same. From that viewer you can also share it, set it as a wallpaper, or save it into your main photo library so it's easier to find later.
Opening a JPEG in a web browser
This one surprises people. Drag any JPG file straight onto an open tab in Chrome, Edge, Firefox, or Safari, and the browser displays it instantly. No app needed. It's the fastest way to view an image when you're not sure what else to use, and it works on every computer.
When a JPEG won't open
If double-clicking does nothing or you get an error, it's almost always one of three things.
The download didn't finish. A file that got cut off partway is incomplete and won't display. Delete it and download it again, ideally on a stable connection.
The extension is wrong. Sometimes a file is named photo.jpg but it isn't actually a JPG inside. This happens a lot with images saved from the web, where a WebP or HEIC file gets a .jpg name slapped on it. The viewer trusts the name, tries to read it as a JPG, and chokes.
The file is genuinely corrupted. If it came off a bad memory card or a failed transfer, the data itself may be damaged, and there's often no recovering it. Go back to the original source and grab a fresh copy if you can, rather than trying to repair the broken one.
How to check the real format
To see what a file really is, open it in a viewer that reads many formats, or run it through a converter that detects the type for you. If a tool tells you your "JPG" is actually a WebP or HEIC, that's your answer. Our online JPG converter reads the file's true format and turns it into a clean, standard JPG that opens anywhere, which fixes the renamed-extension problem in one step.
Two of the usual culprits have their own guides. HEIC is the format iPhones use, and WebP is common on websites. If your problem file turns out to be WebP, our guide to converting WebP to JPG covers the fix. And if you're curious what a JPG actually is under the hood, our explainer on the JPG file format breaks it down in plain terms.
For the vast majority of files, though, there's nothing to troubleshoot. A JPEG is about as universal as a file gets. Double-click it and it opens.