Mollom Client API


The Mollom XML-RPC API interface has been deprecated, and is included here for archival purposes.

To develop clients and services that connect to Mollom, use the Mollom REST API.

Mollom is a quality-assessment and spam- filtering service for user-submitted website content, including comments, contact form messages, and other content.

Registered websites send submitted content to be checked by The Mollom service responds with a rating of either 'spam' or 'ham' (i.e. 'not spam') and a quality score. If Mollom is not fully confident of its spam rating, it will return the third possible answer: 'unsure'. In this case, a website can then ask the submitting user to respond to a CAPTCHA challenge supplied by the Mollom servers. Thanks to the 'unsure' reply and the CAPTCHAs, Mollom avoids legitimate content being incorrectly classified as spam.

Combining text classification with an occasional CAPTCHA has two important benefits: (i) it effectively eliminates the need to moderate messages that Mollom decides to block, reducing the moderation workload, and (ii) because the CAPTCHAs are rare (currently only approximately 4% of human users ever see a CAPTCHA), it makes websites much more accessible.

A key Mollom feature is that all participating websites can send feedback to Mollom, explicitly marking comments as spam, profanity or low-quality. Mollom combines the information sent in by all participating websites and learns from it, preventing future abuse.

Mollom provides an Application Programming Interface (API) for the development of Mollom clients and for the use of its services. This is the documentation of Mollom's client API, but a reseller API is available separately. Please also read and agree to the additional information on the usage guidelines (, the terms of service ( and the privacy policy (