Yahoo! Address Book API

The Yahoo! Address Book (AB) API is a JSON/XML interface for accessing and updating the Yahoo! Address Book using a web service. It can be used to look up addresses for auto-completion of emails, to add addresses for future shipping information, to obtain unique identifiers for network invites, or to sync with another address book.

Note: The Address Book API has been deprecated. The API will still be up and running, but no active development will be supported on this API. Therefore, Yahoo! strongly recommends that you use the Contacts API, which is fully in parity with this API and has more features that you can leverage. The documentation will remain online for some time for reference purposes.

Using the API or Web Service


Typical uses of the API include email address auto-complete and contact look up, social network invitations, phone number look up for mobile messaging and postal addressees for shopping and photo sharing services. The functions supported by the API are as follows:

  • Search/Query: The ability to construct a search and return contact records that match a certain set of criteria based on attribute values. Often used for real time lookup.
  • Updating of Contact Data: The ability to create, modify and delete contact information. The Address Book API includes checks during create or update actions to auto-merge identical contacts to reduce the number of duplicates in a user's address book.
  • Synchronization: The ability to determine if contact information has changed since last access for a specific user for synchronization based applications.

Tools and Documentation

The Yahoo! Address Book API documentation is available in pdf or HTML formats for viewing online. The Yahoo! Address Book API Documentation contains four sections:

  • Overview: A general overview of what the Yahoo! Address Book API is, how it works, and the workflow for developing and publishing your own applications.
  • Getting Started: Basic instructions for setting up access to the Yahoo! Address Book API and examples for creating an auto-complete application. Also check out the following YDN Blog posts for tutorials on getting started with using the Yahoo! Address Book API with PHP and using the Yahoo! Address Book API with Ruby on Rails. Both posts include sample code that can be reused.
  • Developer Guide: The Yahoo! Address Book API supported methods.
  • API Reference: A reference to the Yahoo! Address Book schema and interfaces in the Yahoo! Address Book API and code examples.

Rate Limits

The Yahoo! Address Book API is limited to 500 queries per API key per day.

Terms of Use

Use of the Yahoo! Address Book API is governed by the Yahoo! Address Book API Terms of Use.