Online music videos will now get age ratings in the same way films do, following a government pilot.
Sony Music, Universal Music and Warner Music will send videos to the British Board of Film Classification (BBFC) before putting them on YouTube and Vevo.
Of the 132 videos submitted to the BBFC so far, 56 are rated 12 and 53 classified 15.
Only one video got an 18 certificate - Dizzee Rascal's Couple Of Stack.
It was described as having "strong bloody violence", "gore" and "very strong language".
Examples of videos with the 15 certificate include Calvin Harris's Open Wide, which has "strong bloody violence", sexual references and language, and Meet Me in the Middle by Jessie Ware, which is said to have sexual content.
These age ratings will only be applied to music videos produced in the UK.
International artists who cause controversy with their videos, such as Rihanna with Better Have My Money, won't be affected.
The government says the scheme will "protect children from viewing inappropriate videos on the internet".
Independent labels will now also be taking part in the scheme with a trial lasting six months, the government confirmed.
Videos given an 18 rating won't automatically load in your browser window.
You won't see a black card with an age stamp like you do at the cinema or the start of a DVD, however Vevo and YouTube will display this information on the webpage.
"Britain is a world leader in making exciting and original music, in part because our artists have a freedom to express themselves that we rightly cherish," said Geoff Taylor, chief executive of the British Phonographic Industry.
"While we must continue to uphold this principle, it is equally important that music videos are broadcast in a responsible way and that parents are given the tools to make more informed viewing decisions on behalf of their families."
Mercury-nominated singer FKA Twigs previously told Newsbeat: "I think that the answer to protecting younger viewers is not to ban things, it's to show an alternative.
"I guess with my videos we're talking directly about sexuality and there's nothing wrong with that.
"Why shouldn't younger people learn and explore about what sexuality is as an adult? Why shouldn't they do that?
"We're not living in Victorian Britain, do we want to be repressed? Do we want to have these kids doing weird things behind closed doors or should this be a country that is leading by example in explaining to people?"
Nic Jones of Vevo said the company was committed to making age ratings work "as effectively as possible" and would also look into more age controls.
"We have been working with the participants in this pilot to help them display the BBFC's age ratings on their music videos on YouTube," said Candice Morrissey from YouTube.
"These ratings are in addition to the controls we already provide on YouTube including the ability for uploaders to add age warnings to videos and a restricted mode."
When the scheme was first launched in October 2014, Newsbeat joined Ella on the Run on the set of the video for War of Words in Stoke-on-Trent.
"I think there's two sides to the pilot," she said at the time.
"I understand the reason for it. I would say age ratings would be appropriate because sometimes you don't want your kids to see certain sexual imagery or violence.
"At the same time, I think giving an age rating might actually get people to make even more provocative videos than before as long as they get the proper rating for it.
"So there's two sides to the story, but it's hard to decide which is the better outcome. So we'll see."
David Cooke, director of the BBFC said the organisation is "looking forward to building on the success of the pilot".
Baroness Joanna Shields, the Minister for Internet Safety and Security, said: "Movies in the cinema and music DVDs are age rated to inform the viewer and help parents to make informed choices.
"We welcome this voluntary step from industry to bring internet services in line with the offline world."