What Kadence Blocks does on your site
Kadence Blocks adds a library of layout and content blocks to the WordPress block editor: Row Layout and Section for columns and containers, accordion, tabs, advanced gallery, buttons, info box, icons, countdown, count up, progress bar, testimonials, table of contents, table, Google Maps, Lottie animations and an advanced form. Header and navigation blocks also let you build the site header right in the editor. Every block has per-device settings (desktop, tablet, mobile) for typography, colors and spacing.
On the front end, the plugin only loads the CSS and JavaScript of the blocks a page actually uses. It also ships a design library (ready-made patterns and pages to import), a Style Library since version 3.8.0 to set colors, typography and spacing once, and a free performance optimizer since version 3.6.0: lazy loading of background images and below-the-fold HTML, and image sizes matched to each screen.
The developer, Kadence WP, is part of Nexcess, the parent company of Liquid Web, and also publishes the Kadence theme. Kadence Blocks Pro, a separate plugin, adds the Query Loop (Adv), Advanced Slider, Modal, Video Popup and Post Grid/Carousel blocks, dynamic content, conditional display, custom fonts and icons, scroll animations and the premium design library, among other things.
Which sites Kadence Blocks is a good fit for
Kadence Blocks makes sense when you want rich pages without leaving the native editor:
- Sites running the Kadence theme: theme and blocks share the color palette and global settings, and the design library builds on both.
- Business sites and landing pages: rows, sections, buttons, tabs and testimonials cover most sales pages without a separate page builder.
- Agencies and freelancers: block defaults can be exported from one site to the next, and design settings can be hidden by user role, so clients edit content without breaking the layout.
It is the wrong pick if you want a drag-and-drop visual builder outside the block editor, or if three or four blocks are all you need: the native editor will do. Our WordPress page builder comparison puts Kadence Blocks next to Elementor, Divi and Bricks, and Spectra is its most direct alternative.
Kadence Blocks strengths and limitations
Strengths
- A very complete free version. Layout, form, gallery, header, navigation, table of contents and the design library are all free.
- Assets loaded on demand. Each page only loads the CSS and JavaScript of the blocks it contains.
- A built-in performance optimizer. Lazy loading of backgrounds and below-the-fold HTML, page by page or in bulk.
- Settings built for client sites. Block defaults, import and export, and settings hidden by role.
Limitations
- Content tied to the plugin. The editor no longer recognizes
kadence/*blocks, and they lose their styling, if you deactivate Kadence Blocks. - A long list of published vulnerabilities. More than forty patched flaws according to Patchstack, most of them exploitable with a Contributor account.
- No standalone Pro. The vendor’s pricing page only lists bundles, starting at $350 per year for one site.
- A limited free form. Submissions go out by email, redirect, MailerLite or FluentCRM; saving entries to the database, Mailchimp and Brevo require Pro.
The Kadence Blocks settings we recommend
All of these settings exist in the current free version. General settings live in the Kadence admin menu; the rest are in Kadence Blocks Controls, the K icon in the top right corner of the block editor.
| Setting | Recommended value | Why |
|---|---|---|
| Auto-updates Plugins > Kadence Blocks | Enabled | Security fixes ship often, sometimes several a month. |
| Load Google Fonts Locally Kadence > Settings > Google Fonts | True | Fonts are served from your own server, with no call to Google on every visit. With the Kadence theme, this option lives in the theme instead. |
| Globally Enable The Performance Optimizer Kadence Blocks Controls > Performance Optimizer | Depends on the site | Try it on a few pages first alongside your caching plugin, then compare speed before and after. |
| Exclude this post from optimization Editor, on the page in question | On only for a page that renders badly | Takes one page out of the optimizer without turning it off sitewide. |
| Visibility Settings Kadence Blocks Controls > Block Visibility | Minimum role Editor for design settings | Authors and contributors keep the content, without touching margins or colors. |
| Show Kadence Library For Kadence Blocks Controls | Minimum role Editor on multi-author sites | Keeps writers from importing whole sections into their posts. |
| Captcha block Advanced Form block > Captcha field | Turnstile, reCAPTCHA or hCaptcha with your keys | The form then filters out automated submissions. |
- After turning on local fonts, view a page’s source: no
fonts.googleapis.comaddress should come from Kadence Blocks. - With the optimizer on, open optimized pages in a private window on mobile and desktop, and filter the page list by optimizer status to spot the ones marked “Outdated”.
- Send a test message from every form: it should arrive, and a submission that fails the captcha should be rejected.
- In Users, check who holds the Contributor or Author role: that is the account level most of the plugin’s vulnerabilities require.
Kadence Blocks security: frequent fixes, mostly on the Contributor side
The Kadence Blocks changelog lists a security fix in most releases since summer 2026. The dominant family is stored XSS: a Contributor account slips a script into a block attribute that is not escaped properly. The cases most worth knowing:
- August 2023, fixed in 3.1.11: a file upload possible without an account, published by Patchstack without a CVE number.
- CVE-2023-6964, versions up to 3.1.26: a server-side request forgery (SSRF) through an import function of the design library, with a Contributor account (CVSS 8.5).
- CVE-2026-1857, fixed in 3.6.2: another SSRF, through the GetResponse integration, with a Contributor account (CVSS 4.3).
- CVE-2026-12904, fixed in 3.7.8: a Contributor could read, modify or delete the optimizer data of other content (CVSS 4.3).
- CVE-2026-39742, fixed in 3.8.1: a stored XSS affecting versions up to 3.8.0.2 (CVSS 6.5).
So turn on auto-updates for Kadence Blocks (see our guide to plugin auto-updates) and only give the Contributor role to people you trust. Our article on vulnerabilities in popular themes and their companion plugins puts Kadence Blocks in context. WP Masquerade Pro renames the plugin folder and the kadence-blocks IDs of its scripts and stylesheets, while the kb-* and wp-block-kadence-* classes stay visible: that makes the plugin harder for bots to spot, but it is no substitute for updating.
What WP Masquerade hides for Kadence Blocks
Pro Handled by WP Masquerade Pro only
The free version does not know the traces specific to Kadence Blocks: without Pro, only generator tags are removed, as for any plugin.
Free version
Handled by WP Masquerade Pro only
With Pro
- folder name
- tag IDs
Still visible
- CSS classes
kb-*, wp-block-kadence-*
These traces stay because the plugin needs them to work (scripts, styles, cookies) or because they come from the server.
Kadence Blocks FAQ
Do I need the Kadence theme to use Kadence Blocks?
No, the plugin works with most themes. The Kadence theme adds tighter integration: a shared color palette and font options handled by the theme.
What happens to my pages if I deactivate Kadence Blocks?
The kadence/* blocks stay in your content, but the editor no longer recognizes them and their styling disappears. Before switching tools, plan to rebuild the pages that use them.
How much does Kadence Blocks Pro cost?
The vendor’s pricing page does not offer Kadence Blocks Pro on its own: it is included in bundles with Give, The Events Calendar and LearnDash, from $350 per year for one site up to $999 per year for 100 sites.
Does the performance optimizer replace a caching plugin?
No. Kadence’s documentation describes it as a complement to your caching plugin: it optimizes the content shown first, without caching pages.