Simple Custom CSS and JS

87 Quality Score

Active Installs

26/30

With 600,000 active installs it is one of the most widely used CSS and JS injection plugins in the WordPress ecosystem, which gives it strong real-world exposure.

Update Freshness

25/25

It was updated on 2026-05-20 and explicitly tested against WordPress 7.0, so the maintenance signal is excellent and indicates active upkeep.

User Rating

13/15

An 88 out of 100 from 103 ratings reflects solid user satisfaction, though the sample size is modest given the install base.

Support Health

8/15

Support thread resolution sits at 0 out of 0, meaning there is no public support activity to measure, which is a neutral rather than negative signal.

WP Compatibility

15/15

It supports WordPress 3.0.1 onward, PHP 5.2.4 onward, and is tested with WordPress 7.0, giving it the broadest compatibility range on this list.

Scores higher than 97% of indexed plugins

About

Easily add Custom CSS or JS to your website with an awesome editor.

Active Installs 600k+

Rating ★★★★ 4.4/5

Last Updated 2026-08-20 10:29am GMT

Requires WordPress 4.2+

Tested Up To 7.1

Requires PHP 5.2.4+

Security History

1 known vulnerability, all patched

1 Medium

Most recent: July 24, 2017

View details ▸

What It Does

Simple Custom CSS and JS lets you add sitewide or page-specific CSS and JavaScript through a dedicated editor in the WordPress admin, without editing theme files directly. You can store snippets, target individual URLs or post types, and choose whether scripts load in the header or footer. It is a long-standing utility for theme tinkerers who want a safe place to keep custom code separate from parent theme updates.

Who It's For

This is a good fit for site owners and freelance designers who want to apply custom CSS or JS tweaks, run A/B style scripts, or add tracking pixels without creating a child theme. It works well for blogs, small business sites, portfolios, and online stores where light code injection is part of the workflow. Beginners benefit from the code editor, while developers get a quick place to stash snippets.

Who Should Skip It

If you only need to drop a single analytics or verification script into the header or footer, WPCode (Insert Headers and Footers) is lighter and purpose-built for that. Anyone running a heavily customized site with version-controlled deployments should manage custom CSS and JS through a child theme or a proper build pipeline rather than a database-stored plugin.

The Bottom Line

Simple Custom CSS and JS earns an overall quality score of 86.58 out of 100, backed by 600,000 installs, strong ratings, and current maintenance against WordPress 7.0. The zero public support threads are a minor concern, but for the core job of injecting custom CSS and JS safely, it remains a dependable choice. It is a utility worth keeping in your shortlist, especially if you outgrow the basic Insert Headers and Footers plugin.

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