The acquisition will be used to help Yahoo! expand its services to help clients' online marketing efforts.
It will give Yahoo! additional capabilities to deliver insights and metrics for online campaigns that run across the entire Yahoo! network.
Small-to-medium businesses marketing on the web with Yahoo! will be the first to benefit from using IndexTools as soon as the acquisition is completed.
Bassel Ojjeh, senior vice-president and head of Yahoo!'s strategic data solutions group, said: "We expect that the IndexTools' technology platform will provide our customers the opportunity to more quickly uncover and act on these insights, enhancing Yahoo!'s status as a partner of choice in online marketing and the must-buy for the world’s advertisers."
Additional capabilities are expected to follow throughout the year, allowing third-party developers to monitor and optimise the traffic performance of their applications.