Kelkoo.com was founded in 2000, following mergers with Zoomit, Dondecomprar and Shopgenie.

Within 2 years of launching, Kelkoo became Europe's largest e-commerce website, after Amazon and Ebay, and the largest e-commerce advertising platform both in the UK and Europe. According to Hitwise, the leading online competitive intelligence service, Kelkoo is the UK's favourite shopping comparison site and has been for more than 4 years. In April 2004 Kelkoo was acquired by Yahoo! Inc and is now a wholly owned subsidiary. Kelkoo now operates in 10 European countries and Kelkoo is a one-stop shopping service, which helps shoppers to find, research and buy products online with confidence.