Every WordPress landing page is built out of the same raw material: a hero, some stats, a features grid, a pricing table, a FAQ accordion, a CTA banner. The question that actually decides your stack is not whether you can get those sections, it is where they come from. Kadence Blocks and Spectra are the two most-installed answers to that question: separate plugins, work with any theme, free tier plus a paid tier for the rest. Brndle, the free theme this site maintains, answers it differently: 20 native blocks compiled into the theme itself, no plugin to install, no license to buy, and no way to use them anywhere else.

This is a blocks-only comparison, not a themes-only one. GeneratePress and Kadence the theme came up in our hooks-vs-blocks-vs-Blade post; this one is about what you actually drag into a landing page when you’re building one, section by section, in the block editor. Kadence Blocks and Spectra both have install bases, review counts and years of iteration Brndle cannot claim. It would be dishonest to pretend a 20-block theme-native library competes with either on raw surface area. What it competes on is a different question: what does this cost, per site, forever, and what happens when you switch themes.

In this comparison

What “included in a theme” vs “separate block plugin” actually means
Side by side: block count, pricing, theme lock-in, design tokens
Kadence Blocks: 24 free blocks, now sold inside a Liquid Web bundle
Spectra: 1M+ installs, two products, and a bundle of its own
Brndle’s 20 blocks: free, theme-native, and not going anywhere else
A worked scenario: building the same landing page three ways
The bottom line
Questions about Kadence Blocks, Spectra and Brndle
What should you do next?

What “included in a theme” vs “separate block plugin” actually means

Kadence Blocks and Spectra are both theme-agnostic plugins. Install either one on Twenty Twenty-Five, Astra, GeneratePress, OceanWP, a client’s inherited custom theme, whatever, and you get the same block library. That portability is the entire pitch: an agency standardizes on one plugin, learns its block set once, and reuses that knowledge (and, with Pro, that pattern library) across every client site regardless of which theme each one runs. The cost of that portability is that the plugin has no idea what design tokens your theme defines. It ships its own color palette, its own spacing scale, its own typography controls, layered on top of whatever theme.json the active theme already set up. Keeping the two in sync is a manual, ongoing job.

Brndle’s 20 blocks take the opposite trade. They are registered by the theme itself through one BlockServiceProvider class and rendered through Blade views that read the same theme.json color presets, font pairs and CSS variables every other part of the theme uses. A Hero block’s background and a paragraph’s link color come from the identical token source, because there is no second plugin maintaining a parallel palette. The cost of that integration is that it only exists on Brndle. Switch themes and the blocks don’t come with you, the same limitation GenerateBlocks has on GeneratePress and site-builder blocks have on most page-builder themes.

Neither model is universally correct. A plugin you can carry between client sites is worth real money to an agency with twenty active builds on different themes. A block library that shares your theme’s design tokens by construction is worth real money to a team that standardizes on one theme and wants zero drift between “what the theme.json says” and “what the landing page blocks actually render.” The rest of this post is about what each option costs you today, concretely, not which philosophy wins in the abstract.

Side by side: block count, pricing, theme lock-in, design tokens

	Kadence Blocks	Spectra	Brndle
Distribution	Separate plugin, 600,000+ active installs, 4.8 stars (333 ratings)	Separate plugin (Spectra Legacy / Ultimate Addons for Gutenberg), 1,000,000+ active installs, 4.7 stars (1,872 reviews)	Compiled into the theme, no plugin to install
Free block count	24 block types (Row Layout, Accordion, Advanced Form, Advanced Gallery, Tabs, Testimonials, Icon List, Table of Contents, Advanced Table, Advanced Navigation, Advanced Search, and more)	30+ block types across Core, Content, Post, Social, Forms, SEO and Site Tools categories (Container, Sliders, Content Timeline, Google Maps, Post Carousel, Post Grid, Instagram Feed, Price List, FAQ, How-To, Review, Popup Builder, and more)	20 blocks, fixed set, no additions without writing a Blade view
Pro-only blocks/features	Advanced Query Loop, Advanced Slider, Image Overlay, Modal, Post Grid/Carousel, Product Carousel, Repeater, Split Content, Video Popup, Animate on Scroll, custom icons/fonts, dynamic content, 800+ pattern Design Library	Loop Builder, registration/login forms, and the newer “Spectra Blocks” AI website builder (a separate, newer 60,000+ install plugin built around prompting a full site into existence, then editing natively in Gutenberg)	None. All 20 blocks, free and Pro, do not exist as a category here – there is no paid tier
Current pricing (checked 30 Oct 2026)	Free plugin, or the Liquid Web/Nexcess bundle: $350/yr (1 site) to $999/yr (100 sites), includes The Events Calendar, LearnDash and Give whether needed or not	Free plugin, or Spectra Pro: $69/yr for 3 sites, bundling Astra Pro (theme), Ultimate Elementor Addons and SureForms Agency alongside it. Essential Toolkit + AI: $199/yr intro (10 sites). Business Toolkit + AI: $279/yr intro (1,000 sites)	100% free, GPL-2.0-or-later, no license key, no paid tier at any size
Theme-agnostic?	Yes, works with any WordPress theme by design	Yes, works with “most standard WordPress themes” per its own listing (Astra, Blocksy, GeneratePress named explicitly)	No, Brndle-only, the blocks are not published as a standalone plugin
Design-token integration	Own color/spacing/typography panels per block, independent of the active theme’s `theme.json`	Own global styling defaults and local Google Fonts, independent of the active theme’s `theme.json`	Reads the theme’s own color presets, font pairs and CSS variables directly – one token source, not two

Kadence Blocks: 24 free blocks, now sold inside a Liquid Web bundle

Kadence Blocks is the most-installed of the three at 600,000+ active sites, 4.8 stars across 333 ratings on WordPress.org, and it earns that install count honestly: the free plugin alone covers almost every section a marketing page needs. The current free block roster, per the plugin’s own WordPress.org listing: Row Layout, Section, Accordion, Tabs, Advanced Button, Advanced Form, Advanced Gallery, Advanced Text, Countdown, Count Up, Icon, Icon List, Info Box, Lottie Animation, Posts, Progress Bar, Show More, Spacer/Divider, Table of Contents, Testimonials, Vector Illustration, plus Advanced versions of Navigation, Search and Table. That is 24 named block types, not 20+, and the Row Layout block alone functions as a flexible column/grid system that most of the others compose inside.

Composing a landing page in Kadence Blocks happens entirely in the native block editor:

<!-- A simplified view of what a three-column Row Layout
     looks like in post content. Attribute names and the
     uniqueID suffix are Kadence's own and will vary by build. -->
<!-- wp:kadence/rowlayout {"uniqueID":"_a1b2c3","columns":3} -->
<div class="wp-block-kadence-rowlayout kt-row-layout-id_a1b2c3">
  <!-- wp:kadence/column {"uniqueID":"_d4e5f6"} -->
  <!-- wp:kadence/infobox {"uniqueID":"_g7h8i9"} /-->
  <!-- /wp:kadence/column -->
</div>
<!-- /wp:kadence/rowlayout -->

Pro adds the blocks most relevant to a landing page specifically: Advanced Query Loop (pull in posts or custom post types dynamically), Advanced Slider, Modal, Post and Product Carousel, Repeater, Split Content, Video Popup, plus Animate on Scroll, custom icon and font uploads, dynamic content tags, and an 800+ pattern Design Library an agency can drop into a page and edit rather than build from scratch.

Kadence Blocks marketing page on Liquid Web showing the block editor with Row Layout, Section, Countdown, Icon List and Lottie Animation blocks in the inserter panel — Kadence Blocks’ current marketing page, now hosted on Liquid Web’s software pages rather than a standalone kadencewp.com storefront.

The part worth being precise about, because it changes how you’d actually buy this: kadencewp.com’s own pricing links now redirect (301, permanent) to liquidweb.com/software/kadence/. Kadence is part of Liquid Web’s Nexcess software portfolio alongside StellarWP products like The Events Calendar, LearnDash and Give. There is no standalone “Kadence Blocks Pro only” purchase on that page as of this check. Pricing is one bundle: $350/year for one site, up to $999/year for 100 sites, and every tier includes Kadence Blocks Pro plus The Events Calendar, LearnDash and Give, whether the project needs event ticketing or course software or not. An agency that only wants the block library and the 800+ pattern Design Library is paying for three unrelated products to get it.

Spectra: 1M+ installs, two products, and a bundle of its own

Spectra, built by Brainstorm Force (the team behind the Astra theme), is the larger of the two by raw install count: 1,000,000+ active installations and 4.7 stars across 1,872 reviews for the plugin currently listed on WordPress.org as “Spectra Legacy – Gutenberg Blocks” (plugin slug ultimate-addons-for-gutenberg, its original name). Worth flagging before anything else: Brainstorm Force has split Spectra into two separate products. “Spectra Legacy” is the established, classic block library, the one this comparison is actually about, still being maintained for existing sites. “Spectra Blocks” (plugin slug spectra) is a newer, smaller product at 60,000+ installs, pitched as an AI website builder: “Build a full website with AI, then edit every block natively in Gutenberg.” If you install “Spectra” from the plugin directory today expecting the classic block set, check which of the two you’re getting.

Spectra Legacy’s free block roster is organized into categories on its own listing: Core – Container, Heading, Image, Icon, Buttons, Info Box, Call To Action, Countdown; Content – Sliders, Content Timeline, Google Maps, Inline Notices, Tabs, Taxonomy List, Price List; Post – Counter, Modal Popup, Post Carousel, Post Grid, Post Timeline; Social – Instagram Feed, Blockquote, Social Share, Team, Testimonials; Forms – contact, newsletter signup, suggestion form, reCAPTCHA; SEO – FAQ, How-To, Review, Table of Contents; plus site tools like a Popup Builder, Coming Soon mode, block animations and local Google Fonts. Counted individually that is 30+ named blocks, meaningfully more free surface area than Kadence Blocks, with a visible lean toward SEO-schema blocks (FAQ, How-To, Review all emit structured data) that neither Kadence Blocks nor Brndle match block-for-block.

Pro unlocks the Loop Builder (a dynamic query block comparable to Kadence’s Advanced Query Loop) and registration/login form blocks, plus the premium patterns library and AI tooling described below. Its own FAQ confirms what agencies need to know before standardizing on it: “You can use Spectra with any WordPress theme,” and the plugin’s listing names Astra, Blocksy and GeneratePress by name as themes it’s tested against.

Spectra pricing page showing Spectra Pro at $69 per year for 3 sites, Essential Toolkit plus AI at $199 per year for 10 sites, and Business Toolkit plus AI at $279 per year for 1000 sites — Spectra’s actual pricing page as of this check: Spectra Pro is no longer sold alone either, it’s bundled with Astra Pro, Ultimate Elementor Addons and SureForms Agency at every tier.

Spectra Pro has followed Kadence down the bundle path, just structured differently. The entry tier, Spectra Pro, is $69/year for use on up to 3 websites, and that single price includes Spectra Pro, Astra Pro (the theme), Ultimate Elementor Addons, and SureForms Agency (normally $229 on its own) together, plus premium patterns and kits and an AI platform layer: generate sites with AI, access premium AI designs, customize sites with AI, and spin up “blueprint” and “sandbox” sites. Two higher tiers exist for agencies: Essential Toolkit + AI at $199/year intro pricing for 10 sites, and Business Toolkit + AI at $279/year intro pricing for up to 1,000 sites, each adding more blueprint/sandbox site allowances and support tiers. The honest read: you cannot buy “just Spectra Pro, no theme, no AI platform” at any published tier, the same situation Kadence Blocks is in with its Liquid Web bundle, just with a lower entry price and a different set of unrelated products riding along.

Brndle’s 20 blocks: free, theme-native, and not going anywhere else

Brndle takes neither a plugin-based nor a page-builder-based approach. The theme registers 20 native Gutenberg blocks through a single BlockServiceProvider class, confirmed directly against the project’s source on GitHub (resources/views/blocks/, 20 Blade view files, one per block). Fourteen are marketing/landing-page blocks: hero, stats, features, content-image-split, how-it-works, comparison-table, pricing, testimonials, team, logos, video-embed, faq, cta, and lead-form. Six more are editorial blocks added in later versions for content-heavy pages rather than landing pages: code, pull-quote, timeline, tabs-accordion, post-feed, and card-grid. (If you’ve read Brndle’s own README and landed on “14 blocks,” that figure describes only the original marketing-block wave and is stale; the live source tree has shipped 20 since the editorial blocks landed.)

Every one of those 20 is server-side rendered through a Blade view named after the block slug, registered in a loop rather than 20 separate register_block_type() calls:

foreach ( $this->blocks as $block ) {
    $viewName  = "blocks.{$block}";
    $blockName = "brndle/{$block}";

    register_block_type( $path, [
        'render_callback' => function ( array $attributes, string $content ) use ( $viewName, $blockName ) {
            $attributes = \Brndle\Blocks\AttributeMigrations::apply( $blockName, $attributes );

            if ( function_exists( 'Roots\\view' ) ) {
                return view( $viewName, [
                    'attributes' => $attributes,
                    'content'    => $content,
                ] )->render();
            }

            return $content;
        },
    ] );
}

The practical difference this makes on a landing page: a Brndle Hero block’s background color, button color, and heading font are pulled from the same theme.json presets the rest of the site uses, through the documented filter hooks (brndle/color_presets, brndle/font_pairs, brndle/css_variables). There is no second settings panel defining a parallel “block accent color” that can drift from the theme’s actual brand color, because the block and the theme read the same source. Changing the site’s color palette in Customizer or theme.json updates every block that uses it, automatically, the next time the page renders.

The honest limits: 20 fixed blocks is a real, cohesive design system, not 24 or 30+ block types plus hundreds of premium patterns. There is no Kadence Cloud or Spectra template library equivalent to pull a pre-built section from, no dynamic query loop block, no slider, no modal, no popup builder, and nothing resembling Spectra’s SEO-schema blocks (How-To, Review) beyond the FAQ block’s own JSON-LD output. If your landing page needs a section neither plugin’s free tier covers either, you’re writing a Blade view, the same comfort-with-Laravel-flavoured-PHP assumption any Sage-based theme makes. And critically: these 20 blocks are theme-native, not a standalone plugin. They do not travel to a client’s GeneratePress or Astra site the way Kadence Blocks or Spectra would.

A worked scenario: building the same landing page three ways

Say the brief is an identical SaaS landing page across three agency builds: hero, logo bar, features, how-it-works, pricing, testimonials, FAQ, CTA. Eight sections, nothing exotic.

Build it on a client’s existing Astra or GeneratePress site with Kadence Blocks. Every section composes from free blocks (Row Layout plus Info Box, Testimonials, Accordion, Advanced Button), no purchase required for this scope alone. The honest line item to check before quoting: does the client also want ticketing, courses, or donation forms anywhere on the site, because if the agency isn’t already on the Liquid Web bundle, the $350/year entry tier buys three products to get the one block library actually needed, or you stay on the free plugin and accept no 800+ pattern library, no dynamic query loop, no slider.
Build the same brief with Spectra, on the same kind of client site. The free tier covers it just as completely, arguably with a small edge on the FAQ section specifically since Spectra’s FAQ block ships SEO schema out of the box the way Brndle’s does and Kadence’s Accordion block alone does not. If the agency wants Loop Builder for a dynamic case-studies section, or the premium pattern library to skip hand-building the hero, Spectra Pro at $69/year for 3 sites is the cheapest entry point of the three paid tiers compared here, with the caveat that it also hands you Astra Pro, Elementor addons and a forms plugin you may not use.
Build it on Brndle. All eight sections map directly to included blocks (Hero, Logos, Features, How It Works, Pricing, Testimonials, FAQ, CTA) with zero plugin installs and zero licensing cost, and the whole thing inherits the theme’s color and font tokens by default, no separate styling pass to keep Kadence’s or Spectra’s panels in sync with the theme. The tradeoff to accept going in: this only works because the brief happens to map onto the included set. A ninth section that isn’t one of the 20 means writing a Blade view, and the whole page is locked to Brndle, if the client ever migrates themes, the sections get rebuilt by hand like any other page-builder migration.

None of the three is the wrong call in isolation. The mistake is picking based on which plugin you’ve used before rather than answering two questions first: does this build need to run on a theme other than the one you’re already standardizing on, and does the page need any section outside what the free tier of whichever option you pick actually includes.

The bottom line

Kadence Blocks earns its 600,000+ installs with one of the most complete free block libraries available for any theme, and the thing it actually sells now, the Liquid Web Nexcess bundle, is a materially bigger and more expensive purchase than “Kadence Blocks Pro” used to be. Spectra earns its larger 1,000,000+ install base the same way, with a free tier that edges Kadence’s on raw block count and SEO-schema coverage, and its own paid tier has followed the identical path into a bundle, just at a lower $69/year entry price with Astra Pro and two other products riding along. Both are theme-agnostic by design, which is real, durable value for anyone building across client sites on different themes, and both now require buying products you may not need to get the blocks you do.

Brndle cannot match either one’s install base, review count, or block count, and pretending otherwise would be exactly the kind of overselling this post is explicitly trying to avoid. What it has that neither competitor can offer at any price is 20 blocks that read the theme’s own design tokens by construction, included on day one, with nothing to unlock, ever, and no unrelated product bundled in to make the math work. If your landing page brief fits inside 20 blocks and you’re already building on Brndle, that is free. If it doesn’t, or you need the library to travel to a theme Brndle isn’t running on, Kadence Blocks or Spectra’s free tiers are the honest next stop before either paid bundle.

Questions about Kadence Blocks, Spectra and Brndle

Is Kadence Blocks really free, or do I need Pro to build a real page?

The free plugin is genuinely usable on its own: 24 block types including Row Layout, Accordion, Advanced Form, Testimonials and Table of Contents cover most marketing sections without a purchase. Pro adds the blocks you’d reach for on a more ambitious build: a dynamic query loop, sliders, modals, and the 800+ pattern Design Library. Whether you need those depends on the brief, not on whether the free tier is “really” free.

What is the difference between Spectra and “Spectra Legacy”?

As of this check, Brainstorm Force runs two separate plugins. “Spectra Legacy – Gutenberg Blocks” (ultimate-addons-for-gutenberg) is the established, 1,000,000+ install classic block library this comparison covers. “Spectra Blocks” (spectra) is a newer, 60,000+ install AI website-building product. If you search the plugin directory for “Spectra,” confirm which one you’re installing before you plan a build around its block set.

Can I use Brndle’s 20 blocks on a different WordPress theme?

No. They are registered by the Brndle theme itself and are not published as a standalone plugin, unlike Kadence Blocks or Spectra, which work on any theme by design. This is the central tradeoff of the theme-native approach: tight integration with Brndle’s design tokens, zero portability elsewhere.

Do Kadence Blocks and Spectra conflict if I install both?

They can run side by side without fatal conflicts since each registers its own namespaced blocks (kadence/ vs uagb/), but doing so doubles your editor’s block inserter, your CSS payload, and your settings panels for overlapping functionality like accordions and testimonials. Most builds pick one plugin as the primary block library rather than running both.

Is Brndle’s README “14 blocks” figure wrong?

It’s outdated, not wrong at the time it was written. The original README summary describes the first wave of 14 marketing blocks (hero, stats, features, pricing, FAQ and the rest). Six editorial blocks, code, pull quote, timeline, tabs/accordion, post feed, and card grid, shipped in later releases and the live resources/views/blocks/ directory on GitHub confirms 20 block views today. Always check the source tree over a README summary for a fast-moving open-source project.

Which has better SEO-schema blocks: Kadence Blocks, Spectra, or Brndle?

Spectra, on breadth: its SEO category ships dedicated FAQ, How-To and Review blocks that each emit their own structured data, free. Brndle’s FAQ block emits JSON-LD schema too, but it’s the only one of its 20 blocks built around schema output. Kadence Blocks’ free tier doesn’t ship a dedicated SEO-schema category at all; Table of Contents is the closest free block with SEO relevance.

Do I need coding skills to use any of these three?

To compose a page from the included blocks, no, for all three. Kadence Blocks and Spectra are built explicitly for no-code page assembly in the native editor. Brndle’s 20 blocks work the same way once built into a page. Writing a new block or a custom Blade view for Brndle, or deeply customizing a Kadence or Spectra block beyond its panel options, assumes developer comfort in each respective stack.

Can I use Kadence Blocks or Spectra inside a Brndle site?

Yes. Both are standalone plugins and will install and run on Brndle like any other block theme, since all three register standard Gutenberg blocks rather than replacing the block editor with a proprietary canvas. You’d be running Brndle’s 20 native blocks alongside whichever plugin’s blocks, with the design-token integration advantage only applying to Brndle’s own blocks.

Is the AI site-building angle (Spectra Blocks, GeneratePress AI) relevant to this comparison?

Only tangentially. Spectra Blocks (the newer 60,000+ install product) and GeneratePress AI both sell prompt-to-site generation layered on top of their respective block editors. Brndle ships no AI site-building feature, and Kadence Blocks’ own listing doesn’t foreground one either. If AI-assisted page generation is a hard requirement, that narrows your options before block count or pricing even enters the decision.

How do I migrate a landing page between these three block libraries?

Expect a rebuild, not a conversion. Text and images carry over through standard WordPress export/import, but section markup does not: a Kadence Row Layout, a Spectra Container, and a Brndle Hero block are three unrelated block types with no shared structure, so each library’s sections get rebuilt by hand in the destination. We cover the mechanics of that kind of rebuild, measured on a real test page, in our page builder to block theme teardown.

What should you do next?

Check current pricing and block counts yourself before quoting a build, all three vendors ship fast enough that parts of this post will be stale within months: Kadence Blocks via Liquid Web, Spectra pricing, and Brndle’s source on GitHub. If you’re evaluating Brndle specifically for a design-system-first build, our piece on building a design system an AI agent can follow covers how the filter hooks and theme.json tokens the 20 blocks depend on are meant to be extended, and our GeneratePress vs Kadence vs Brndle comparison is the companion read if you’re deciding on the theme underneath, not just the block library on top.

Kadence Blocks vs Spectra vs Brndle’s 20 Native Blocks