Extending the Code block with syntax highlighting rendered on the server, thus being AMP-compatible and having faster frontend performance.
As of April 2026, Syntax-highlighting Code Block (with Server-side Rendering) is a WordPress code plugin with 1.0K+ active installations and a 5/5 rating from 26 reviews. It has been downloaded 40K+ times in total. Requires WordPress 6.6+ and PHP 7.4+. Available on WordPress.org since 2019. Downloads are down 56% this week. Top alternative: WPCode – Insert Headers and Footers +….
This plugin extends the Code block in WordPress core to add syntax highlighting which is rendered on the server. Pre-existing Code blocks on a site are automatically extended to include syntax highlighting. Doing server-side syntax highlighting eliminates the need to enqueue any JavaScript on the frontend (e.g. Highlight.js or Prism.js) and this ensures there is no flash of unhighlighted code (FOUC?). Reducing script on the frontend improves frontend performance, and it also allows for the syntax highlighted code to appear properly in AMP pages as rendered by the official AMP plugin (see also ampproject/amp-wp#972) or when JavaScript is turned off in the browser.
This extended Code block uses language auto-detection to add syntax highlighting, but you can override the language in the bloc…
no one wants to conduct a real study to see how many of use hate the code block.
missed just a download and/or copy button.
also for theme, maybe is best to update “usage instruction”! only after some search I understood can be changed via customized menu.
anyway, looks so good.
ty.
Thanks for this. It’s really nice.
Works great, thanks !
I confess, I’ve been a happy user of Code Syntax Block for quite a while — a plugin which the author, Weston Router, clearly states that Syntax Highlighting (Code Block) is based upon.
Alas, however, all the pages I had with the older plugin would suffer from an inevitable rendering slowdown — there is so much Javascript on web pages these days that such a slowdown is inevitable, and this is especially true to those scripts that attempt to recognise the language automatically — something that will consume plenty of CPU cycles on the browser. Parsing the language is also no mean feature by itself (I know, I’ve been doing some experiments for some code editors, and, believe me, it’s tough!).
So why force the end-user to bear the burden of all that work? It makes much more sense to pre-render everything on the server, and then let the web server send the already-parsed HTML from its cache. That way, the end-user will already have everything on their browser, no need to wait for parsing!
Also, if you ‘forget’ to set the language that your code is in (it happens…), the auto-detecting feature will only run on the server, and just once, when you save the post you’re writing. Even if it takes a fraction of a second more to save, think of how much time all those users will save when they get the already-rendered page!
So, this plugin is definitely recommended. As a bonus: if you are already using some sort of code block on your WP setup, once you turn off whatever plugin you were using, Syntax Highlighting (Code Block) will immediately pick it up and start its magic (you might need to open and save all the pages you’ve got code on, though — I’m not quite sure if that’s really the case). That means zero effort (beyond saving) — what you already had will continue to work. And, naturally enough, when you disable this plugin, your code block will just revert to the internal WP code block instead — nothing will be ‘lost’ that way!
If you’re still hesitant and reading this to the end… while you wasted your time here, think of how many of your users would have saved their time if you already had this plugin installed 🙂
| WordPress | 6.6+ requiredTested up to 6.9.4 |
| PHP | 7.4+ required |
For the plugin’s changelog, please see the Releases page on GitHub.
Plugin data sourced from WordPress.org. Analysis and metrics by PluginSift.