Kit

aid: kit
url: https://raw.githubusercontent.com/api-evangelist/kit/refs/heads/main/apis.yml
name: Kit
kind: company
description: >-
  Kit (formerly ConvertKit) is an email marketing and creator platform. The Kit API V4
  exposes subscribers, broadcasts, sequences, tags, custom fields, forms, purchases,
  and webhooks. V3 is deprecated.
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
tags:
  - Email Marketing
  - Creator Economy
  - Newsletters
  - Automation
  - Subscribers
created: '2026-05-08'
modified: '2026-05-30'
specificationVersion: '0.19'
apis:
  - aid: kit:kit-api-v4
    name: Kit API V4
    humanURL: https://developers.kit.com/v4/api-reference
    baseURL: https://api.kit.com/v4
    tags:
      - Email Marketing
      - Subscribers
      - Broadcasts
      - Sequences
      - Tags
      - Forms
      - Webhooks
    description: >-
      Kit API V4 supports OAuth 2.0 and API key authentication. It provides cursor-based
      pagination, bulk requests, and async processing across subscribers, broadcasts,
      sequences, tags, custom fields, forms, purchases, and webhook subscriptions.
      It supersedes the deprecated V3 API.
    properties:
      - type: Documentation
        url: https://developers.kit.com/v4/api-reference
      - type: Authentication
        url: https://developers.kit.com/v4/api-reference/authentication
      - type: Webhooks
        url: https://developers.kit.com/v4/api-reference/webhooks
      - type: Migration
        url: https://developers.kit.com/v4/api-reference/v3-to-v4-upgrade-guide
      - type: OpenAPI
        url: openapi/kit-openapi.yml
      - type: AsyncAPI
        url: asyncapi/kit-webhooks-asyncapi.yml
  - aid: kit:kit-api-v3
    name: Kit API V3 (Deprecated)
    humanURL: https://developers.kit.com/v3/api-reference
    baseURL: https://api.convertkit.com/v3
    tags:
      - Email Marketing
      - Subscribers
      - Deprecated
    description: >-
      The legacy ConvertKit V3 API is deprecated and slated for discontinuation; new
      integrations should target V4.
    properties:
      - type: Documentation
        url: https://developers.kit.com/v3/api-reference
      - type: Deprecation
        url: https://developers.kit.com/v4/api-reference/v3-to-v4-upgrade-guide
common:
  - type: GitHubOrganization
    url: https://github.com/kit
  - type: Website
    url: https://kit.com/
  - type: Portal
    url: https://developers.kit.com/
  - type: SignUp
    url: https://app.kit.com/users/signup
  - type: Pricing
    url: https://kit.com/pricing
  - type: Plans
    url: plans/kit-plans-pricing.yml
  - type: RateLimits
    url: rate-limits/kit-rate-limits.yml
  - type: FinOps
    url: finops/kit-finops.yml
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com