The tool marries Microsoft’s ad-serving data with demographic information from ComScore’s online panel of web users.

ComScore’s chairman and co-founder, Gian Fulgoni, said: “Brand advertisers need the ability to evaluate reach and frequency by audience composition in ways that are actionable and accountable. Current online reach and frequency metrics are typically computed at the site level.

“Measuring reach and frequency at the ad placement level is more precise because it shows the reach of the ad campaign that can actually be achieved, the true potential frequency and the specific demos of that audience.”

The firms said the Reach and Frequency Planner will provide brand advertisers with a “complete front-to-end media buying and planning process” for the digital environment, using metrics similar to those used in traditional media.

Scott Howe (pictured), Microsoft’s corporate vice president in the advertiser and publisher solutions group,said: “The perception that traditional branding metrics are not possible or meaningful for digital media is misguided. We believe online advertising won’t maximise its appeal to brand marketers until the basic metrics they’ve relied on for years in digital media plans.”