Data Field Types and Input Formats

When submitting contact data via the KlickTipp Listbuilding API, all values must match the field types and field keys configured in your KlickTipp account.

The KlickTipp API does not provide endpoints to retrieve field definitions or metadata.
Your integration must therefore ensure that values are sent in the correct format.

This document describes all supported field types and their expected input formats.

General Rules

Field keys must exactly match the keys configured in the KlickTipp account
Values must conform to the expected field type
Invalid formats will result in validation errors
Date and time fields must always be sent as Unix timestamps

Supported Field Types

Field type	Comment	Example
Line	String, single-line text	`Alex`
Paragraph	String, line breaks allowed	`Line 1 \n Line 2`
E-mail	Valid email string, must contain `@`	`alex.example@klicktipp.example`
Number	Integer, send as numeric value, not as string	`100`
Decimal number	Integer, send value multiplied by 100. The UI displays value divided by 100 with `.` (UI: `19.99`).	`1999`
URL	Absolute URL, must start with `http://` or `https://`	`https://www.klicktipp.example`
Date	Unix timestamp in seconds, do not send formatted date	`755222400`
Date & time	Unix timestamp in seconds, not milliseconds	`1715603400`
Time	Seconds since midnight (`0-86399`)	`52200`

Important Validation Notes

Use Unix timestamps in seconds only, for example 755222400, not 755222400000.
For numeric custom fields, send numeric values as numbers when possible, for example 100 instead of "100".
Decimal number fields expect a scaled integer (factor 100), not a literal decimal string. Send 1999 to display 19.99 in the UI.
Phone values such as +491701234567 are text values and should be treated as strings.

Date and Time Fields

Although date and time values are displayed as formatted strings in the KlickTipp UI, the API always expects Unix timestamps.

This applies to the following field types.

Time
Date
Date & time

Sending formatted date strings instead of timestamps will result in field validation errors.

Common Validation Mistakes

Sending formatted date strings instead of Unix timestamps
Sending decimal values to integer number fields
Using invalid URLs without protocol
Sending text values to numeric fields
Using incorrect or outdated field keys

If a value does not match the expected field type, the API will reject the request with a field validation error.

Summary

All values must match the configured field type in the KlickTipp account
Date and time fields must always be sent as Unix timestamps
Invalid formats result in field validation errors, not silent coercion
Correct field mapping is the responsibility of the integration
The API does not expose field metadata or field types