Naspers co-led a series D round that increased the web ranking provider's overall funding to $40m.

UK-based web ranking company SimilarWeb closed a $15m series D round on Tuesday co-led by South Africa-based internet services provider Naspers and private investor David Alliance.

SimilarWeb has raised $40m since its incorporation in 2009, with Naspers providing $18m of series C funding in February 2014.

The company’s other backers include Docor International Management, the venture capital firm set up by charity Van Leer Group Foundation, as well as individual investors Moshe Lichtman, Yossi Vardi, Liron Rose and Omer Kaplan.