That's according to a forecast being made by FTI Consulting, a company that projects online spending. Online ad spending will climb to $41.8 billion this year from $37.5 and to $55.6 Billion by 2018. FTI says digital advertising will grow at a 10% clip through 2018. TV is expected to grow at a rate of 4.2% which would put it at about $38.5 Billion this year and $45.5 Billion in 2018. If these predictions hold true online ad spending will become the number one media spending category by overtaking Television.