DoubleClick Ad Planner is a free, online measurement product “To further our commitment to provide reliable data in DAP, we’ve submitted it for accreditation by Media Rating Council – is an advertising industry group that works to accredit audience measurement services that’re valid, reliable, and effective[…]For our traffic measurement, Ad Planner uses hybrid measurement methodology that combines direct-measured site traffic, through Google Analytics data that publishers’ve chosen to opt in to provide us, and sample aggregated data from Google products and services. We currently’ve over 10,000 sites contributing direct measured opt-in data to Ad Planner. Our sample data comes from variety of sources including anonymized, aggregated Google Toolbar data from users who’ve opted in to enhanced features, opt-in anonymous GAs data, opt-in external consumer panel data, and other 3rd-party market research. All of this data’s aggregated over millions of users and is powered by computer algorithms. The breadth and reliability of this aggregated data means that our traffic measurements are among most accurate in the industry,” notes Google.