Knock is a real estate technology company that helps homeowners buy and sell their homes with less stress and more certainty. Knock uses data science to price homes accurately, technology to sell them quickly, and a dedicated team of professionals to guide homeowners through the process. Knock also offers a trade-in program, called the Knock Home Swap, which allows homeowners to buy their new home before selling their old one. Knock is headquartered in San Francisco, California and was founded in 2015.