Bloglines was a web-based news aggregator for reading syndicated feeds using the RSS and Atom formats.

Users could subscribe to the syndicated feeds for free using a web browser.

Bloglines offered an application programming interface that maintainers of web could use to write software to read feeds, search its database of feed entries, and ping the service when a website was updated.

Mark Fletcher, former CEO of ONElist, founded the site in June 2003 and sold it in February 2005 to Ask.com/InterActiveCorp.

[4] However, on November 4, 2010, on-line marketing company MerchantCircle announced that it would assume control of Bloglines.