Kadence Blocks vs Spectra

Kadence Blocks and Spectra are both block libraries that add extra layout, content, and design blocks to the native WordPress block editor, rather than replacing it the way a full page builder does - but each is now tied to a different business model. Kadence Blocks has been folded into Liquid Web's broader Kadence product line, sold as bundles with a theme, security tools, and commerce features. Spectra, from Brainstorm Force (the team behind the Astra theme), has split its own product line: the plugin most people still install under this name is now labeled “Spectra Legacy,” receiving only security and compatibility updates, while new features ship in a separate, newer Spectra product. Kadence Blocks currently holds roughly 650,000 active installs against Spectra Legacy's larger base near 1.49 million.

Mechanically, both plugins do a similar job: they register additional Gutenberg blocks - containers, sliders, post grids, forms, and more - alongside starter templates, without swapping out the editor entirely. The real difference is where each company is putting its resources. Nexcess (Liquid Web) sells Kadence Blocks as one piece of a larger Kadence ecosystem, with security, backups, and WooCommerce tools bundled into higher tiers. Brainstorm Force has moved active Spectra development to a newer plugin, leaving the classic install path - which is what most existing users and this listing represent - in maintenance mode.

Quick verdict: Choose Kadence Blocks if you want a block library that's part of a broader, actively-marketed ecosystem with theme, security, and commerce add-ons available as you grow. Choose Spectra if you already run it and only need a stable, well-supported block library - but if you're picking a block plugin fresh today, check Brainstorm Force's newer, actively-developed Spectra product before defaulting to this legacy listing.

Kadence Blocks vs Spectra at a glance

Installs above are StatWP's own estimates, drawn from WordPress.org's bucketed reporting rather than an exact published figure, and update automatically rather than reflecting a fixed snapshot.

The two plugins' opposite momentum lines up with the story above rather than contradicting it: Kadence Blocks' recent install growth tracks with Liquid Web's push to bundle it into the wider Kadence suite, while Spectra Legacy's decline lines up with users migrating toward Brainstorm Force's newer, actively-developed Spectra product instead of staying on this listing.

Feature and starting price at a glance

Pricing and feature claims above are each vendor's own, pulled from their product pages rather than StatWP data, except Spectra's current price, which could not be verified directly during research and shouldn't be assumed. One thing worth flagging: Kadence's $99/year figure prices the whole Kadence bundle (theme, blocks, and more), not a Kadence-Blocks-only license, so it isn't a direct apples-to-apples number against a standalone block-plugin price.

What does Kadence Blocks actually do?

Beyond the install and ratings numbers, Liquid Web's own site (which now hosts Kadence's product pages) positions it around a few specific mechanics:

• Global style controls and pre-built starter templates for building pages inside the block editor.

• WooCommerce-focused “Shop Kit” tools aimed at turning site visitors into buyers.

• Membership and subscription tools for gating and monetizing content, part of the wider Kadence suite rather than the Blocks plugin alone.

• Security features - firewall, two-factor authentication, and daily backups - bundled into higher Kadence tiers.

Liquid Web, which now owns the Kadence brand through its Nexcess division, markets it as a complete ecosystem rather than a standalone block plugin, citing more than 600,000 creators and a leading web-accessibility rating.

What does Spectra actually do?

Per its own WordPress.org listing, the plugin at this exact slug - now labeled Spectra Legacy - covers a broad, if frozen, set of mechanics:

• Layout blocks such as containers, sliders, and tabs for structuring pages.

• Content and post blocks, including counters and post grids for dynamic listings.

• Form and SEO blocks, including FAQ, How-To, and Review schema blocks.

• Social blocks like Instagram feeds and testimonial displays.

• Site tools such as a popup builder, coming-soon mode, block animations, and locally-hosted Google Fonts.

Brainstorm Force's own listing is explicit that this version receives “security and compatibility updates and full support, but no new features,” with active development now happening in a separate, newer Spectra product.

What features does each one have that the other doesn't?

Kadence Blocks' clearest differentiator is ecosystem breadth: because it's sold as part of the wider Kadence suite, buyers who go premium get bundled security, backups, and WooCommerce tools that Spectra doesn't offer at any tier, block library or otherwise.

Spectra Legacy's clearest differentiator, somewhat counterintuitively, is stability. Brainstorm Force has explicitly frozen new-feature development on this exact plugin while continuing security and compatibility support, giving long-time users a lower-risk, unchanging base to build on rather than the faster pace of change Kadence Blocks is currently going through.

Which should you actually use?

If you're starting a new site and want a block library that comes with a growing ecosystem of add-ons - security, backups, commerce tools - available as you scale, Kadence Blocks' current bundled model gives you a path to that without switching plugins later. If you already have a site running the classic Ultimate Addons for Gutenberg/Spectra plugin and don't need new features, staying on Spectra Legacy is a reasonable, low-risk choice for now. But if you're choosing a block plugin fresh today, look at Brainstorm Force's newer, actively-developed Spectra product before defaulting to this legacy listing.

Frequently asked questions

What is the difference between Kadence Blocks and Spectra?

Kadence Blocks is a Gutenberg block library sold as part of a broader Kadence product ecosystem that also includes a theme, security tools, and WooCommerce add-ons. Spectra, at this exact plugin listing, is now labeled Spectra Legacy - it still works and receives security updates, but Brainstorm Force has moved active feature development to a separate, newer Spectra plugin.

Is Spectra better than Kadence Blocks?

Not straightforwardly - it depends what you value. Spectra Legacy has the larger install base and a broad, stable block library, but it isn't receiving new features. Kadence Blocks is smaller but growing quickly and backed by an actively expanding ecosystem. Neither is a strictly better version of the other.

Is Spectra still being actively developed?

The plugin at this listing, Spectra Legacy, is not receiving new features - only security and compatibility updates - according to its own WordPress.org description. Brainstorm Force's active development has moved to a separate, newer Spectra product.

Does Kadence Blocks require the Kadence theme?

No - Kadence Blocks works as a standalone block library with most WordPress themes, though it's marketed alongside the Kadence theme and other Kadence ecosystem products.

Is Kadence Blocks free?

Yes, a free version is available, with premium tiers unlocking additional design controls and the wider Kadence ecosystem - security, backups, commerce tools - starting around $99/year for the bundled suite.

See the live, current numbers for either plugin any time on StatWP's Kadence Blocks page or StatWP's Spectra page, or run this comparison yourself with StatWP's compare tool.