Meridian is a new cPanel theme you can try from your existing (Jupiter) cPanel: look for the "Try the new Meridian theme" button. It reorganizes cPanel's dozens of tools into nine sections, leads with a dashboard that tells you what actually needs attention, and adds a command-style search and a floating AI assistant. It's optional. If you don't like it, a "Classic cPanel Theme" button takes you straight back to Jupiter.
What changed
Jupiter (the current default) organizes tools by category in a sidebar: Files, Databases, Domains, Email, Metrics, Security, Software, and so on, each a flat list of icons. Meridian collapses that into nine sections: Dashboard, Websites & Apps, Softaculous Apps Installer, WordPress, Email, Files, Databases, Security, Performance. Instead of hunting through a grid of icons, most day-to-day work happens inside one of those sections.
The biggest functional change is the Dashboard. Rather than a static account summary, it surfaces action-required cards when something's wrong: a "DNS not resolving" card links straight to Check DNS, a "No Certificate" card links to Fix SSL Issue. Below that sits a suggested-next-actions list, then your disk and bandwidth usage and general account overview.
Websites & Apps is the other structural change. Instead of jumping between separate Domains, Zone Editor, SSL, and PHP tools, each site gets its own set of tabs: Overview, SSL, Email, DNS, Files, Backups, Alias, and Settings. Settings is where PHP version, force-HTTPS, redirects, FTP accounts, the WordPress admin account, and per-folder directory privacy live, plus a "Danger zone" for the website's root folder. It's the same underlying features as Jupiter, grouped per-site instead of per-tool.
Security works the same way: a Security Score plus SSL status and Web Firewall status up top, then three tabs, SSL Certificates (Automatic SSL), Protection (the web application firewall, IP Blocker, Hotlink Protection), and Advanced (SSH keys, active sessions).
Ask AI and search
Meridian adds a top search bar (open it with Cmd+K) that jumps you to any tool or setting by name, which is faster than paging through sidebar sections once you know roughly what you're looking for. There's also a floating "Ask AI" assistant that answers questions like "What domains do I have" or "How much disk space am I using." It comes with its own disclaimer that responses may be inaccurate, so treat it as a starting point, not a replacement for checking the setting yourself before you save a change.
Dark mode
Meridian includes a light/dark/system toggle next to the search bar. This is purely visual and doesn't change where any tool lives.
What still needs Classic
Meridian's nine sections cover the tools most people use most often, but some tools are Classic-only for now: Cron Jobs, the full Zone Editor, MultiPHP INI Editor, JetBackup, Git Version Control, and Awstats. You can reach these through the top search, or you can switch themes entirely with the "Classic cPanel Theme" button and switch back later.
If you're chasing down a PHP upload limit or an upload_max_filesize change, for example, that's still a MultiPHP INI Editor job, reachable via search from Meridian or directly from Classic. See what PHP version should I use for WordPress for more on picking a version before you touch limits.
Should you switch
Try it if you want the dashboard's "what's wrong right now" view, or you manage multiple sites and like having each one's SSL, email, DNS, and files under one set of tabs instead of four separate tools. Stick with Classic if you're used to Jupiter's layout, rely heavily on tools that are still Classic-only, or you don't want to relearn where things are mid-project. Switching back and forth costs nothing, so there's no downside to trying Meridian.