Kit Integrations: App Store, API V4, Purchases, WordPress and AI Connectors

Kit connects to other tools in four ways: an app store inside the product, a public API, purchase integrations with checkout platforms, and AI Connectors for AI assistants. This page explains each, from Kit's help centre read on 9 October 2026, with what each plan unlocks.

The short answer

Interface	Free	Creator	Pro
Kit App Store, free apps	Yes	Yes	Yes
Kit App Store, paid apps	No	Yes	Yes
API (V4)	Yes	Yes	Yes
Purchase integrations (Shopify, Stripe, Gumroad, Squarespace)	Yes	Yes	Yes
AI Connectors	View only	Yes	Yes
Facebook Custom Audiences sync	No	No	Yes

From the free plan article, plan comparison and app store overview ^{[6] [3] [55]}.

## The Kit App Store

Apps are installed from the Apps menu and are "built by a community of developers" ^[55]. You can search by name or category, filter by feature and sort by popularity. Some apps require a paid plan; on Free their button reads Upgrade to install ^[55]. The overview gives KitBoard as an example, a kanban-style view of subscribers by tag for creators with a sales pipeline ^[55].

Zapier needs a paid plan

Kit's Zapier article is explicit: it needs "a paid Kit account to connect with Zapier and all other apps" ^[57]. That is stricter than the free plan article, which says free apps remain available on Free ^[6]. Treat Zapier as a Creator feature. Kit's own example of a Zap is a purchase in another app adding a tag, which then starts a visual automation ^[57], and visual automations are Creator features in any case ^[3].

Zapier itself has a free plan that may be enough for simple Zaps ^[57]; its paid plans are a cost on top of Kit.

## The API

Kit's current API is V4. It offers a full Broadcast API with "full HTML support and segmentation targeting", cursor pagination and consistent error handling ^[56]. V3 "will remain accessible for the foreseeable future" but is no longer developed, and the two cannot be used interchangeably ^[56]. API access is on every plan, Free included ^[6].

When to use it. Adding subscribers from your own app, tagging them from a quiz, sending a broadcast built by a script, or pulling subscriber data into a spreadsheet.

Choosing between the app store, the API and Zapier

Most creators never need the API. The order that saves the most time is: look in the Kit App Store first, because an app installs in a few clicks and is maintained by its developer ^[55]; then Zapier, which Kit documents and which connects thousands of tools without code ^[57]; and only then the API, for workflows no app covers ^[56].

The API is the right choice when you control the other system: your own site's signup flow, a member area that should tag subscribers, or a script that builds and sends a broadcast. V4's Broadcast API supports full HTML and segment targeting ^[56], which makes it suitable for newsletters assembled automatically.

Working with API keys

V4 keys are created in Developer Settings: add a new key, name it, and copy it at once, because "you'll not see it again" after leaving the screen ^[56]. Keys can be reset or deleted later ^[56]. Use one key per integration, so one can be revoked without breaking the others, and store keys in your application's secret settings rather than in code.

V3 keys and V4 keys cannot be used interchangeably ^[56]. An older plugin or script that still uses V3 will keep working "for the foreseeable future", but Kit reserves the right to deprecate it ^[56]. Plan the move when you next touch the integration.

Purchase integrations

The Purchases feature records what subscribers buy on Shopify, Squarespace Commerce, Stripe and Gumroad ^[28]. With Shopify connected, customers who have bought at least one product sync to Kit, and each gets a product tag named after what they bought; past purchases can be imported at installation ^[58]. That lets a creator send a sequence to everyone who bought a course, or exclude buyers from a launch.

Course platforms connect too: Kit publishes guides for Kajabi and Teachable ^{[61] [62]}, and Zapier links thousands of other tools ^[57].

Course platforms

Creators who sell courses usually host them elsewhere and use Kit for the email around them. Kit publishes integration guides for Kajabi and Teachable ^{[61] [62]}. The pattern is the same: a purchase on the course platform tags the buyer in Kit, and the tag starts an onboarding sequence, which needs Creator ^[3]. Kit's own commerce can also sell the course directly, with payment plans of at least two instalments ^[42].

WordPress

Kit's own plugin, listed on WordPress.org as "Kit (formerly ConvertKit)", holds 4.8 stars from 90 ratings, 83 of them five-star . It embeds forms and landing pages, and Kit documents publishing broadcasts as WordPress posts and the reverse ^{[59] [60]}. For a creator whose site runs on WordPress, this is the most mature integration Kit offers.

AI Connectors

AI Connectors use the Model Context Protocol to connect Kit to "Claude, ChatGPT, Cursor, and other MCP-compatible AI assistants" ^[39]. They work on Creator and Pro; on Free you can connect and browse, but running a tool shows an upgrade prompt ^[39]. Each tool is annotated as read-only, destructive, idempotent or open-world, so the AI client can ask before acting ^[40]. You can review, pause and revoke access at any time ^[39].

Landing pages on your own domain

Kit hosts landing pages and a newsletter site, and its WordPress guides cover placing a Kit landing page on your own domain and embedding forms in posts ^[59]. For a creator without a website, Kit's newsletter site lets visitors subscribe and read past newsletters published to the web, with a customisable address ^[36]. Kit does not offer a full website builder.

Sending domain and deliverability

Kit recommends authenticating a verified sending domain and adding a DMARC record, and documents both ^{[67] [66]}. Double opt-in is the default on forms and landing pages, and Kit recommends keeping it on ^[65].

Facebook audiences, a Pro feature

Pro syncs Kit segments to Facebook Custom Audiences ^[3]. A creator who advertises can build a lookalike audience from buyers, or exclude existing subscribers from ads. At 1,000 subscribers Pro costs $40 a month more than Creator; at 10,000, $50 ^[2]. If you spend more than that each month on Facebook ads, the sync is likely to pay for itself by keeping ads away from people already on the list.

Integrations and data protection

Every integration moves subscriber data to another company. Kit's own transfers of EU, UK and Swiss data are covered by its Data Processing Addendum ^[64]; the apps you install have their own terms. Install only what you use, and remove apps you no longer need from the Apps menu.

Three integrations, priced

A WordPress blogger collecting subscribers. Plugin plus Kit Free: $0 up to 10,000 subscribers ^[6] .

A course creator on Teachable who wants a post-purchase sequence. Teachable integration plus a sequence: Creator, $39 a month at up to 1,000 subscribers ^{[62] [3]}.

A team syncing segments to Facebook ads. Facebook Custom Audiences sync: Pro, $79 a month at up to 1,000 subscribers ^[3].

Which integration for which creator

Creator	Start with
Blogger on WordPress	The Kit plugin
Course creator on Teachable or Kajabi	The course platform's Kit integration [62] [61]
Merchandise on Shopify	The Shopify app, with product tags [58]
Selling a few digital products	Kit's own commerce, no integration needed [2]
Custom membership site	The V4 API [56]
Many small tools	Zapier, on a paid plan [57]
Working through an AI assistant	AI Connectors, on a paid plan [39]

The pattern is to use the integration closest to where the purchase or sign-up happens, and let Kit's tags carry the information into sequences.

Shopify buyers and marketing consent

When Kit syncs a Shopify store, customers who have bought at least one product become Kit subscribers with product tags, and past purchases can be imported at installation ^[58]. Buyers who did not accept marketing are marked with their own tag ^[58]. A buyer is not the same as a subscriber who asked for a newsletter; send marketing only to those who agreed, or the complaint rate rises and verification reviews follow ^[7].

Common integration mistakes

1. Building on API V3. It is no longer developed; start on V4 ^[56].
2. Importing every Shopify buyer as a marketing subscriber. Kit's Shopify integration tags buyers who did not accept marketing; respect that tag ^[58].
3. Installing a paid app on Free. It needs a paid plan ^[55].
4. Letting an AI assistant run destructive tools unreviewed ^[40].

Integrations on the free plan, in practice

On Free, a creator can use the V4 API, connect purchase integrations that tag buyers, embed forms with the WordPress plugin, and connect an AI assistant to browse its tools ^{[6] [28] [39]}. What a free account cannot do is act on those tags automatically, because visual automations and sequences need Creator ^[6], nor connect Zapier, which Kit's Zapier article reserves for paid accounts ^[57]. The integrations collect data on Free; Creator is what makes them do work.

Our verdict on integrations

Kit integrates well with the tools creators already use: WordPress, course platforms, Shopify and Stripe. The friction is the paid line, which sits in front of Zapier, paid apps and AI.

Integration costs to budget

Kit's own integrations cost nothing beyond the Kit plan, but several of them need Creator: Zapier, paid apps and AI Connectors ^{[57] [55] [39]}. Zapier and many apps carry their own subscriptions on top. A creator automating sales through Zapier and Kit pays two vendors; doing the same with Kit's native purchase integrations pays one ^[28].

Security of integrations

Each integration is a key to your list. Give apps and AI assistants the narrowest access that works, review AI Connector actions before approving them, as Kit itself advises ^[39], and remove apps you no longer use. For EU, UK and Swiss subscribers, Kit's own transfers are covered by its Data Processing Addendum ^[64]; each app's handling of that data is a matter for the app's terms.

Integrations compared with beehiiv

beehiiv offers its API on every plan with a published rate limit, webhooks from its first paid plan, and a Send API only on Pro. Kit offers its V4 API, including a Broadcast API with full HTML, on every plan ^[56], and leaves the automation that consumes integration data to Creator. For a developer sending generated newsletters, Kit's Broadcast API on any plan is the more accessible of the two.

## How integrations affect our score

Our integrations score for Kit is 3.9, the highest among creator platforms in our email category: an open API on every plan, an app store, purchase tagging from four checkout platforms, a WordPress plugin rated 4.8, and AI Connectors with safety annotations. It loses points for paid apps and AI Connectors being paid-plan features and for Facebook audience sync being Pro only.