The man bun and comb-over are big already, and Google predicts they'll only get bigger. Those are among conclusions from Google's analysis of millions of searches on hair amid a growing universe of YouTube video tutorials on hair styles and products.

While the man bun and the comb over are the two top hair style trends identified by Google, the latter has been more of a slow build since 2011, while the former has burst upon the collective consciousness far more rapidly in 2015. While Jared Leto may have been the first celebrity associated with the man bun, Harry Styles is now "owning the look," according to Google.

In many minds Donald Trump, a 2015 search phenomenon in his own right, owns the comb-over. But that's really not what this men's hair trend is about, according to Marc Speichert, the Google managing director-global partner who as former L'Oreal chief marketing officer was on the receiving end of such analytics for years until he made the move to Google in 2013.

The comb-over interest comes from far younger men with fully intact follicles, with top celebrities associated in "comb over" searches include Christiano Rinaldo, David Beckham and Justin Timberlake.

While the man bun is growing faster, the comb-over beats it 10.3 million to 4.1 million in terms of YouTube views of the top five tutorial videos on each. Google also finds search activity on man buns remarkably spread out nationwide, while "comb over" searches are concentrated on the coasts -- especially California -- suggesting it has more room to move inland.

"You see more and more sophistication around searches for comb-overs," Mr. Speichert said. "The search queries are getting longer and longer. Men are trying to understand how to do a low fade, high fade, a short or long comb-over."

Such men's hair-related searches are the most prominent things Google found in this year's hair research, interesting in itself given that, as Mr. Spechert well remembers from his days at L'Oreal USA, men here have been slow to hop aboard the global growth in personal-care spending.

"I think the market is just in the beginning of picking up," he said, and an increase in searches related to men's hair is a sign of that. Products related to comb-over include pomades and styling gels, while products linked to man buns include sponge wax, light cream, sea spray and styling powder.

"There's a ton of content out there" regarding man buns and comb-overs, he said, but relatively little advertising or content from brands. He sees that as an opportunity -- for the brands and Google.

As he also recalls from L'Oreal days, search trends do spawn marketing initiatives. L'Oreal Feria's line of ombre hair coloring products was sparked by working with Google on search analysis years ago. While ombre remains a trend in this year's Google hair analysis, balayage -- a softer look achieved by not saturating color through the hair until the very tips -- looks to be bigger now.

Other big things in hair-color searches are decidedly less natural looking, such as shades of purple, silver and burgundy. Google predicts silver hair -- a holdover from Rihanna's 2013 look -- may not have much more staying power, but purple, fueled by Katy Perry's 2015 look, could have more.

Braids are big too -- particularly box braids and goddess braids -- the former exemplified by Beyonce and Keri Hilson.

"The markets are moving very fast, and it's getting tougher and tougher to innovate, because there's more and more fragmentation in beauty," Mr. Speichert said. "The more we can help clients identify what trends are so they can jump on them early on, that's the opportunity."