To change your WordPress theme, go to Appearance, then Themes, in your admin screens. Click Activate on a theme you've already installed, or select Add New, find one, install it and activate that. The change goes live the moment you click Activate, so preview first and don't activate a theme whose preview is blank.
Which route you take depends on where the new theme is coming from. It might already be sitting on your site, it might be one you need to go and find, or it might be a file someone has handed you. Pick the section that matches and ignore the other two.
Switching to a theme that's already installed
This is the shortest of the three, because everything you need is on one screen.
- Log in to the WordPress Administration Screens.
- Select the Appearance screen.
- Select Themes, where your installed themes appear.
- Use Live Preview to see your site with its own content.
- Click the Activate button.
Step four is optional in the sense that nothing forces you to do it, but it's how you get a look before the change is real. Your selection becomes active immediately, so whatever you see after that click is what your visitors see too.
If you've made changes to your current theme's own files, stop and read about what a WordPress child theme is before you switch, so you know where work like that belongs.
Finding and installing a new theme
Use this one if you're browsing for something new. There's more detail in our walkthrough on installing a WordPress theme, but this is the sequence from start to finish.
- From Appearance, then Themes, select Add New.
- Use the Search or Filter options to find a theme you'd like.
- Click Preview to see what it looks like.
- Click Install to upload it to your site.
- Click Activate when you're ready for it to go live.
Installing and activating are two separate decisions. Install only puts the theme on your site, and it's Activate that changes what the public sees. That gap is useful, because it means you can install a candidate, look it over and walk away without anybody noticing.
Uploading a zipped theme you already have
If you've been given a theme as a file, or you've downloaded one from somewhere else, this is your route.
- From Appearance, then Themes, select Add New.
- Use the Upload Theme button at the top of the page.
- Upload the zipped copy of the theme.
- Click Activate to switch to it.
Be choosy about where that zip came from, and only upload a file from someone you trust.
Your old theme is still an installed theme after you switch, so it stays on the same screen if you want to go back. And if you've only come here because you want to adjust one thing about the look of your site, it may be simpler to change the text colour and keep the theme you've got.
Why a blank preview means stop
The catch sits in the preview step. If the preview of a theme comes up blank, WordPress says not to activate that theme without investigating, because your site may not display correctly.
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It's tempting to read a blank preview as a glitch in the preview itself and go ahead anyway. Don't. Activate takes effect straight away, so if the warning was right, the first you'll know about it is a site that's not displaying as it should, with visitors already looking at it.
So find out why the preview is blank before you go any further. If you can't get to the bottom of it, choose a different theme. Add New will give you others to look at, and a theme that won't preview isn't worth the gamble.
Frequently asked questions
Can two themes be active at the same time?
No, you're limited to a single active theme, so switching on a new one takes over from the one you had.
What's the difference between Preview and Live Preview?
Preview is the link alongside Install when you're browsing for a theme. With Live Preview you're looking at your own site and its content, which makes it the better test.
Do I have to install a theme before I can activate it?
Yes. Activate is the step that comes after a theme is on your site, so a theme you've only previewed can't go live yet.
What file format does an uploaded theme need?
A zipped copy. Unzipped folders aren't what the Upload Theme button asks for.
How do I go back to my old theme?
Open Appearance, then Themes, and click Activate on the one you had before. That change is immediate too, so preview it if you've edited anything in the meantime.
Can I look at a theme without installing it?
Yes. Click Preview while you're browsing, and leave Install alone until you've made up your mind.
