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Kit Custom Fields API

The Custom Fields API from Kit — 4 operation(s) for custom fields.

Kit Custom Fields API is one of 16 APIs that Kit publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Custom Fields. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, authentication docs, and a changelog.

This API exposes 6 operations across 4 paths. It is described by OpenAPI 3.2.0, at version 4.0.

Requests are made against a single base URL, https://api.kit.com.

6 operations 4 paths 0 schemas 1 DELETE1 GET3 POST1 PUT

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
API Version
4.0
Base URL
https://api.kit.com/v4
Authentication
API Key, OAuth 2.0
Resource Areas
1

Authentication & Security 2

Kit Custom Fields API declares 2 security schemes for authenticating requests. An API key is passed in the header as X-Kit-Api-Key (API_Key). It supports OAuth 2.0 (OAuth2) using the authorizationCode flow, exposing 2 scopes.

  • API_Key — Authenticate API requests via an API Key
  • OAuth2 — Authenticate API requests via an OAuth token

Paths & Operations 6

Across 4 paths, the API surfaces 6 operations — 1 DELETE, 1 GET, 3 POST, 1 PUT. Each is listed below with its method, path, parameters, and response codes.

Custom Fields 6
POST
/v4/bulk/custom_fields
Bulk create custom fields
body → 200202401413422
POST
/v4/bulk/custom_fields/subscribers
Bulk update subscriber custom field values
body → 200202401413422
GET
/v4/custom_fields
List custom fields
4 params → 200401
POST
/v4/custom_fields
Create a custom field
body → 200201401422
DELETE
/v4/custom_fields/{id}
Delete custom field
1 param → 204401404422
PUT
/v4/custom_fields/{id}
Update a custom field
1 param body → 200401404422

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

convertkit-custom-fields-api-openapi.yml Raw ↑

Other APIs Kit publishes across the network.

Kit Accounts API
Kit Broadcasts API
Kit Email Templates API
Kit Forms API
Kit Posts API
Kit Purchases API
Kit Segments API
Kit Sequence Emails API
Kit Sequences API
Kit Snippets API
Kit Subscribers API
Kit Tags API
Where this information came from

This is an independent, third-party profile of Kit Custom Fields API, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.

The Kin Score and Agent Readiness rating are independently calculated assessments of a company's public API artifacts, scored against a published rubric. They are not certifications, endorsements, security assessments, or audits.

Corrections, re-scores, and removal are free — no partnership or purchase required, and you do not need to justify the request. A removed company is recorded as unrated, never scored zero for having asked. Acknowledgement within one business day; removal within two.

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