Otter Blocks vs Kadence Blocks
Both plugins add serious blocks to the native WordPress editor. The real difference is where each one draws the line between free and paid. Otter ships the working features in the free plugin. Kadence ships the blocks free and puts most of the functionality behind Kadence Blocks Pro.
Free forever on WordPress.org. Otter Pro from $69 a year with a 30 day money back guarantee.
Free in Otter, paid in Kadence
What is free in Otter, and what it costs in Kadence
Kadence has a generous block library. What it gates is the part that makes a block do something: storing what people submit, deciding who sees what, and connecting to your mailing list.
Both plugins keep the autoresponder in their paid version. We list it because a comparison that only shows the rows we win is not much use to you.
What you get without paying anything
Both lists below are the free download, with nothing bought. Block counts are the figure each publisher advertises for its own free plugin.
Otter Blocks, free
26+ blocksKadence Blocks, free
30+ blocksKadence advertises more blocks, and five of the six it leads with are free in Otter too. The count is not the thing that decides a build. What decides it is which of those blocks still works once you need it to store a submission or hide itself from logged out visitors.
Where each feature actually lives
Read this as a map of paywalls rather than a scoreboard. Rows where both plugins charge, and rows where Kadence is ahead, are marked as such.
Four reasons to choose Otter Blocks
Your form data stays yours, for free
Every submission Otter receives is written to your WordPress database and listed under Otter Blocks in wp-admin. Kadence needs Blocks Pro before a submission is stored anywhere other than your inbox.
The mailing list is not an upsell
Connect a form to Mailchimp or Brevo on the free plugin. In Kadence both providers are Pro submit actions, so a newsletter signup form means a licence.
Conditional content without a licence
Otter gives you eight visibility conditions in the free plugin, covering logged in state, user role, date range, post meta and more. Kadence keeps Conditional Display in Blocks Pro.
Popups at the entry price, not the top tier
Otter has a free Popup block. Kadence popups live in Kadence Conversions, which is bundled into the Elite plan at $499 a year.
What each side costs
Otter Pro
Priced on how many sites you run. Introductory pricing, renewals at full price.
Kadence
Priced on how much of the product stack you want. Now sold by Liquid Web.
How to read those numbers
Compare like for like. A WooCommerce build costs $69 with Otter Pro and $299 with Kadence, because Shop Kit sits in the middle tier. Popups are free with Otter and arrive at $499 with Kadence. If you also want a theme from the same publisher, ThemeIsle makes Neve: its drag and drop header and footer builder is free, and Neve Pro adds mega menus with sticky and transparent headers. Worth knowing that the header builder inside Kadence Essentials is free in the Kadence theme as well, so the $99 is really buying the extra header elements, mega menus and Blocks Pro.
Moving from Kadence Blocks to Otter
You do not have to rebuild the site in a weekend. Both plugins can run at the same time while you move page by page.
Install Otter alongside Kadence
Otter registers its own blocks and does not touch existing Kadence markup. Nothing on your live pages changes.
Rebuild the pages that hit a paywall
Start with anything blocked by a Kadence Pro feature: forms that need stored entries, sections that need visibility rules, popups.
Point your forms at Otter
Rebuild the form with an Otter Form block, set the save location to database, and reconnect Mailchimp or Brevo.
Retire the Kadence blocks you no longer use
Once a page is fully on Otter, remove the leftover blocks. Keep Kadence installed for as long as any page still depends on it.
When Kadence is the better pick
Three cases where we would point you at Kadence instead.
Common questions
Is Otter Blocks actually free?
Yes. Otter Blocks is on WordPress.org and the free plugin includes forms with stored submissions, Mailchimp and Brevo, eight visibility conditions, the Popup block, per block custom CSS and the AI tools. Otter Pro adds the WooCommerce builder, dynamic content, the autoresponder, file upload and Stripe form fields, and CSV export of submissions.
Can I run Otter and Kadence Blocks together?
Yes. They register separate blocks and do not conflict, which is the easiest way to migrate. Running two block libraries does load two sets of assets, so it is worth removing the one you stop using once a page no longer needs it.
Will switching break my existing Kadence layouts?
No. Installing Otter leaves Kadence markup untouched. A Kadence block only stops rendering if you deactivate Kadence Blocks, so keep it installed until every page has been moved across.
Does Otter store form submissions without Pro?
Yes. Otter writes every valid submission to your WordPress database in both the free and Pro versions, and any administrator can read them under Otter Blocks in wp-admin. Exporting them as CSV or XML is the part that needs Otter Pro.
Do I need an API key to use the AI features in Otter?
Yes. Otter does not resell AI, so you connect your own provider account, either through the native WordPress connector or with an OpenAI key. There is no credit ceiling from ThemeIsle, but your provider bills you for what you use. Kadence works the other way round: it includes credits, starting at 250 lifetime credits on the free plugin, and meters what you generate.
What happens to my site if I let Otter Pro lapse?
Your pages keep rendering. You stop receiving Pro updates and support until you renew. Otter Pro is introductory priced, so renewals are at the full list price shown on the pricing page.
How we checked this
Verified August 2026 against primary sources: the WordPress.org listings for otter-blocks and kadence-blocks; ThemeIsle documentation for the free versus Pro feature list, Form blocks and marketing integrations; the Otter Pro pricing page; Kadence documentation for database entries, the Advanced Form block, block level custom CSS and AI credits; and the Kadence pricing page. Neve figures come from the Neve header builder documentation. Capabilities and prices change often, so tell us if you spot something stale and we will correct it.
Try the free plugin before you compare licences
Install Otter Blocks, build one form, store one submission and set one visibility rule. That is the whole argument, and it costs nothing to test.
Free forever on WordPress.org. Otter Pro from $69 a year with a 30 day money back guarantee.