# Overview

This documentation provides an overview of the KlickTipp APIs and helps you choose the right integration approach for your use case.

It is intended for **tech-savvy marketing professionals and developers** who want to integrate KlickTipp into websites, backend systems, or automation platforms.

## What is this API?

The KlickTipp APIs allow external systems to interact programmatically with KlickTipp in order to:

- Add, update, and manage contacts
- Assign or remove tags to control automations
- Trigger opt-in and unsubscribe processes
- Integrate KlickTipp into custom backends, CRMs, and marketing workflows


Depending on the use case, KlickTipp provides **two distinct APIs** with different scopes and authentication models.

## What are the Prerequisites?

To access the KlickTipp API, you'll need KlickTipp [Premium](https://app.klicktipp.com/bestellen) or higher. Please note that our API functionality is therefore not available with the Standard version of KlickTipp.

## Which API should I use?

### Listbuilding API – for simple contact acquisition

Use the **Listbuilding API** if you want to:

- Add contacts via signup or opt-in forms
- Handle lead magnets or newsletter registrations
- Integrate KlickTipp into landing pages or no-code tools
- Work with a **simple API key** instead of full authentication


The Listbuilding API provides a **restricted and safe interface** focused on contact subscription and opt-in handling.

**Limitation:**
The API is best suited for working with global contact fields. It does not provide any endpoints to retrieve the IDs of custom fields, which makes dynamic or advanced field mappings with custom fields impractical.

**Best for:**
Lead capture, opt-in flows, simple integrations

→ **Documentation:**
[Listbuilding API Reference](/listbuilding-api)

### Management API – for full control and automation

Use the **Management API** if you need to:

- Manage contacts, tags, and custom fields
- Build advanced or bidirectional integrations
- Control automations and lifecycle logic
- Integrate KlickTipp deeply into your backend or CRM


The Management API provides full access to KlickTipp resources and supports multiple authentication models:

It allows authentication for your own usage via Username and Password, as well as authentication for partner integrations using a Developer Key together with a Customer Key.

**Best for:**
Advanced integrations, backend systems, automation platforms

→ **Documentation:**
[Management API Reference](/management-api)

→ **How-To (Partner Integrations):**
[Authenticate using Developer Key & Customer Key](/guides/management-api)

## What are common Use Cases?

### Subscribe Contacts

Add or update a contact in KlickTipp and trigger the associated opt-in process.

Typical scenarios:

- Website signup forms
- Lead magnets
- External tools collecting contact data


→ Depending on the use case, this can be done via:

- **Listbuilding API**
[Add or Update Contact via SignIn](/listbuilding-api#operation/api.subscriber.signin)
- **Management API**
[Add or Update Contact](/management-api#operation/api.subscriber.create)
[List Opt-in Processes](/management-api#operation/api.optin.index)
[List Tags](/management-api#operation/api.tag.index)
[List Data Fields](/management-api#operation/api.customfields.index)


### Manage Segmentation with Tags

Assign or remove tags to control KlickTipp automations.

Typical scenarios:

- Triggering email or SMS sequences
- Segmenting contacts based on behavior
- Reflecting events from external systems (e.g. purchases, status changes)


→ This use case is primarily handled via the **Management API**.

- **Management API**
[Manage Tags](/management-api#tag/tags)


### Unsubscribe Contacts

Unsubscribe a contact from further communication.

Common scenarios:

- One-click unsubscribe links
- GDPR-compliant opt-out handling
- Synchronizing unsubscribe events from external systems


→ Depending on the use case, this can be done via:

- **Listbuilding API**
[Unsubscribe Contact via SignOff](/listbuilding-api#operation/api.subscriber.signoff)
- **Management API**
[Unsubscribe Contact](/management-api#operation/api.subscriber.unsubscribe)


## How can I start?

The following tutorials help you get started with real-world integrations:

- [How to Create an API Key - Secure & Easy Integration](/guides/listbuilding-api)
- [How to authenticate and access the Management API](/guides/management-api-authentication)
- [Building Robust Integrations with the KlickTipp API](/guides/management-api)


This overview is intended to help you **choose the right API**, understand common use cases, and navigate the KlickTipp API documentation efficiently.