XO Group Inc. (formerly The Knot Inc.) is an American media company that publishes multi-media content for couples who are planning weddings, creating a home, and starting a family. The company generates revenue through online advertising, merchandising, registry services, and publishing. The company headquarters are located in New York City, with offices in several locations in its domestic American market as well as in international markets such as for example China.

David Liu, his wife Carley Roney and their business partners, Rob Fassino, and Michael Wolfson founded The Knot Inc. in 1996. They found that the internet could facilitate and reduce anxiety in the process of wedding planning between couples. After the startup received seed financing from AOL, the partners launched The Knot brand as a portal on AOL. In 1997, TheKnot.com launched on the internet.

Next, the company launched an online gift registry in partnership with QVC and published its first book, The Knot Complete Guide to Weddings in the Real World. In December 1999, the company raised $35 million in an initial public offering.

On December 2, 2000, the company launched its own bridal magazine and went public. The Knot Weddings Magazine is published four times a year and is sold on newsstands.

In 2001 The Knot Inc. acquired WeddingPages, Inc., a publisher of regional bridal magazines, to expand its magazine offerings to local markets. Today, The Knot publishes regional magazines in 17 markets in the US. Online, the company hosts wedding vendor listings in its online directories.

In 2004, the company launched a television series, Real Weddings from The Knot, on the Oxygen Network, and in 2005 it launched a streaming online video channel, The Knot TV, that runs on TheKnot.com. In 2009, the company launched a wedding planning show, called The Knot LIVE, which streams in real time to TheKnot.com from its New York City headquarters once a week.

In April 2005, the company became listed on the NASDAQ Stock Market with the ticker symbol "KNOT."

The Nest brand launched in 2005 with a website, and a magazine followed in 2006. The brand serves cohabitating couples and newlyweds with lifestyle content about home decor, finance, cooking, entertaining and relationships. The brand also has two books in print, The Nest Newlywed Handbook and The Nest Home Decor Handbook.

In 2005, The Knot created a CD of wedding music called "The Knot Collection of Ceremony & Wedding Music." The Company also partnered with American Express to offer a co-branded rewards card for The Knot and The Nest.

In 2006 the company acquired WeddingChannel.com which included its registry platform and helped to consolidate the bridal media industry.

In 2008, the company launched TheBump.com to serve expectant and new parents. The Bump Pregnancy Guides feature pregnancy-related content and local pregnancy and baby resources in a pocket-sized magazine distributed through OBGYN offices across the country.

The Knot celebrated its 20-millionth member milestone in June 2010.

In June 2011, the company transferred its common stock listing to the New York Stock Exchange (NYSE) with the symbol "XOXO".

Mike Steib joined XO Group as president in July 2013 and assumed the role of CEO in March 2014.

In October 2015, XO Group announced the acquisition of GigMasters, an online marketplace for event vendors, and a partnership with Jetaport, the discounted hotel room block booking service.

XO Group Inc. publishes wedding planning, nesting, and baby related content on multiple media platforms.