How to Install a Theme in Ghost CMS

The process is simple: download a zip file, upload it to Ghost Admin, activate it. Five minutes, maybe less. But if this is your first time, a few small details can trip you up. This guide covers exactly what to do, in order.

Before You Upload Anything

You need a theme file in .zip format. Keep it zipped. Ghost unpacks it automatically, and uploading an unzipped folder will not work.

If you are still picking a theme, start with the ThemeLib marketplace. There is a good mix of free Ghost themes and premium options, and the featured themes page is a useful shortlist if you want something curated rather than browsing the full catalog. Every theme there is built for Ghost specifically, which matters more than it sounds. Generic themes ported from other platforms often cause compatibility problems on upload.

Installing a Ghost CMS Theme Step by Step

Step 1: Open Design & Branding

Log in to Ghost Admin at yourdomain.com/ghost. Click the gear icon at the bottom-left to open Settings. Select Design & Branding, then click Change theme in the bottom-right corner.

Step 2: Upload the Zip File

Click Upload theme in the top-right corner of the Themes panel. Select your .zip file. Ghost uploads it and runs an automatic compatibility check in the background.

If the upload fails, Ghost will show you an error. Nine times out of ten it is a compatibility issue between the theme and Ghost 6. Check that the theme was built for Ghost 6 before anything else. Themes built for Ghost 4 or 5 will often fail validation without any changes from you.

Step 3: Activate

Click Activate. The theme goes live immediately.

Previous uploads stay saved under the Installed tab. Handy if you want to switch back without uploading the file again.

Quick Customization After Activation

Go back to Design & Branding. Most themes let you change colors, fonts, and layout directly from that panel. No code needed.

For anything the panel does not cover, use Settings, Code Injection to add custom CSS. Changes made there survive theme updates. Changes made directly inside theme files do not, so Code Injection is the safer habit to build from the start.

One last thing: preview the site in an incognito window before you move on. Ghost Admin adds a toolbar that can shift your layout slightly. An incognito window shows you exactly what a new visitor sees.