The Lookup API allows you to retrieve detailed information about phone numbers. This includes carrier information, line type (e.g. mobile, landline, VoIP), portability status, and optionally caller name information. This data can be valuable for validating phone numbers, enhancing user profiles, and making informed decisions about communication channels.

With a single API call, you can access comprehensive phone number intelligence to improve your user verification processes and reduce fraud risks.

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API

The Prelude v2 API is a REST API and uses standard HTTP features and statuses.

The current URL is https://api.prelude.dev/v2.

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Authentication

To perform requests on the API, you need to provide a v2 API key in the Authorization header.

You can create an API key in the Dashboard, under the API Keys section of the settings.

Example request
curl --request POST \
     --url 'https://api.prelude.dev/v2/*' \
     --header 'Accept: application/json' \
     --header 'Authorization: Bearer <API_KEY>'

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Errors

Prelude uses conventional HTTP statuses to indicate the success or failure of a request:

  • Codes in the 2xx range indicate success.
  • Codes in the 4xx range indicate an error that failed given the information provided (e.g. required parameter was omitted or an authentication failed).
  • Codes in the 5xx range indicate an error with Prelude's servers (these are rare).

The Prelude API returns errors using a JSON object in the response body with a machine-readable code and a human-readable message and a param field.

See Errors for more details as well as a list of all possible error codes.