Nickelodeon is undergoing its biggest makeover in 25 years.

The kids’ cabler and its sister nets will unveil a new scheme in fall to replace its “splat” identity — which was first introduced in 1984.

Branding will connect Nickelodeon, Nick at Nite, Nicktoons, Nick Jr. (formerly Noggin) and TeenNick (formerly the N), all of which will use similar-looking lower-case logos.

According to Cyma Zarghami, prexy of Nick and MTV Networks’ Kids and Family Group, the decision to streamline the network identities came after they started putting all of the channels’ logos on the same business card — and decided that it looked like a mess.

“We wanted to clean it up and allow Nick to be the stamp on all of these channels,” she said.

That ultimately meant jettisoning the familiar Nickelodeon “splat.”

“In asking ourselves if everything could live under the splat, we decided that the splat was dated,” she said. “It just couldn’t be done in a streamlined way.”

Decision to update comes as Nickelodeon celebrates its 30th anniversary. It also comes as Nick rebrands Noggin into Nick Jr. and the N into TeenNick in September — putting “Nick” into all of its channels’ names for the first time.

“With Nick turning 30, it felt like this was the year (for an update),” Zarghami said.