Visible Measures, an online video advertising platform, announced on Tuesday that it has secured $21.5 million in funding, led by DAG Ventures with strong participation from existing investors Advance Publications, Inc., owners of Conde Nast, General Catalyst Partners, Mohr Davidow Ventures, Northgate Capital, and new investor Commonfund.

Over one hundred brand advertisers, including P&G, Ford, Goldman Sachs, Microsoft, and Unilever, have adopted Visible Measures’ ad platform, Viewable Media, to promote their video ads as content across hundreds of media properties.

Visible Measures also sells software to measure the performance on online video by showing how long viewers watch and how they interact with online video ads.

Headquartered in Boston, Visible Measures has 100 employees across seven offices in North America and Europe.