Syzygy was appointed alongside ad agency M&C Saatchi to assist London 2012 in its bid to bring the Olympic Games and Paralympic Games to the UK.
The web site (www.london 2012.org.uk) replaces a holding site and it will play an important role in communicating information about the bid and providing visitors with up-to-date information on the progress it is making.
The initial phase of the relaunched web site will go live on 16 January with news updates and information about the bid. Later phases will launch innovative interactive elements on the web site.
Stephen Priestnall, managing director of syzygy, said: "This is a very prestigious project to win; it's great to be part of such a talented team working to deliver a project that's so important to London and the UK."
Cathy Gibbon, web and e-marketing manager at London 2012, added: "We needed an internet partner that could deliver on front-end creative, but would also deliver to a challenging timescale."