Video streaming firm Roku has launched a new measurement tool designed to tempt ad budgets away from traditional TV, revealing audiences missed by TV ads

The 'Activation Insights' tool shows advertisers how many more people they could reach by shifting budgets from TV to over-the-top, or streaming internet TV.

“We’re working with partners, helping them understand and quantify how much viewing is moving from linear to OTT,” says Alison Levin, VP of sales and strategy at Roku. “So, brands can become whole again and find audiences they’ve been losing.”

The measurement tool can analyse how many times a brand’s ad was viewed by Roku users watching traditional TV during a 90-day period.

Then it can calculate how many more unique viewers the brand could have reached by advertising on its over-the-top streaming platform.

Over-the-top TV has grown rapidly during the past decade, leading to a rise in so-called ‘cord cutters’ (people who don’t watch through cable or broadcast TV, but stream video through devices like the one from Roku).

In the U.S., 205 million people will watch some form of over-the-top TV in 2019, whether that’s through YouTube, Hulu, Netflix and others, according to eMarketer’s latest stats.

The OTT market will grow 2.5 percent this year, eMarketer says, and reach 72 percent of all U.S. internet users.

Roku has a growing advertising business through its streaming video boxes that reach 29 million households, as of the end of last quarter, which was up 40 percent year over year, according to the company’s latest earnings report.

Roku also expects to top $1 billion in ad revenue in 2019.