The UK’s online safety watchdog, Ofcom, has launched an investigation into TikTok over children’s risk of exposure to harmful content.
The inquiry focuses on TikTok’s "age inference" system, which estimates a user's age by analysing activity.
Ofcom has questioned the adequacy of these checks, suggesting the method may fail to correctly detect many children, leaving them vulnerable to harmful content.
TikTok, for its part, has insisted it is "confident that we meet our Online Safety Act obligations".
Kate Davies, Ofcom’s group director for strategy and research, told BBC Radio 4’s Today programme: “We found that some methods of age checks being used by social media are not working well enough.
“We have serious doubts about them and so we have launched an investigation into TikTok.”
She added: “What a lot of social media services are doing is using something called age inference, which is where they look about at the behaviour of somebody on their site and use that to judge the age, and we have questions about where that can work.
“It is not in our guidance as an effective method of age check.”
A potential sanction is a fine of up to 10 per cent of worldwide revenue, but a “proper robust process” still needs to be followed.
A TikTok spokesperson said: “We strictly enforce age-appropriate experiences through expert-informed platform rules and advanced age inference technologies, in line with major industry peers.
“In the eight years since TikTok launched in the UK, we have invested billions in platform safety.
“We are confident that we meet our Online Safety Act obligations and will work with Ofcom to demonstrate this.”
Ofcom’s latest investigation has been launched as the regulator warned in a wider report that children are able to use search engines to easily find pornography sites which do not have age checks.
Almost a year on from rules on age checks coming into force, Ofcom has said around a quarter of the UK’s most popular pornography services in the UK had none in place.
Since July 25 last year, all sites and apps in the UK which allow pornography have been required under the Online Safety Act to have age checks in place to protect children from accessing harmful content.
But search services are not required under the Act to use what Ofcom described as “highly effective age assurance” to prevent access to pornographic content by children.
The regulator’s research found that a third of results returned on the first page of Google and more than half on search service Bing were to pornography sites without age checks or other protections such as blocked access for UK users.
The watchdog said both firms will work with Ofcom “as a priority on practical solutions to tackle the discoverability of porn sites without age checks via their services”.
When age checks were first required 12 months ago, the regulator said a simple tickbox to say a user was over 18 “will no longer be enough”.
Recommended stronger methods included facial age estimation where a user shows their face through a photo or video; permission from a user for banking information to be checked to verify age; credit card age checks; and email-based age estimation.
But Ofcom has said “too many services” still have either no or inadequate age checks in place.
While 64 out of the top 100 most popular pornography services in the UK had age checks in place as of June this year, a further 10 geo-block UK users – meaning they cannot access the sites – this leaves 26 sites with no age checks in place.
Research published by the regulator last year found 8% of children aged eight to 14 in the UK visited an online pornography site or app in a month – including around 3% of eight to nine-year-olds.
Ofcom said it had continued to track 701 children of this age on their visits to websites and apps via smartphones, tablets and computers between October 2025 and March this year.
It found half of the 8% who visited pornography sites only visited those with age checks in place.
Because the vast majority of visits to pornography services were for under 30 seconds, Ofcom said the short durations suggested many child users were moving quickly between sites “potentially in search of a site they could access without an age check”.
The watchdog said it had fined seven providers of 24 pornography sites in the past year more than £4 million for failure to comply with age checks.
Asked how much had been paid in fines to date, the regulator said that, as recovery of fines is an ongoing live process it was currently unable to give any further update.
Ofcom has the power to impose fines on firms of up to £18 million or 10% of their qualifying worldwide revenue – whichever is greater – and can have sites blocked or restricted in the UK in the most serious cases.
Ofcom’s chief executive, Dame Melanie Dawes, said: “Age checks are a cornerstone of the UK’s online safety laws. When implemented properly, our evidence shows that age checks are helping to create a safer life online for children in the UK.
“But the job is not done and tech companies need to go further. Too many services have no or inadequate age checks in place, which is not good enough. And search engines must urgently work with us to solve the problem of children finding porn sites without age checks too easily via their results pages.
“As the UK prepares for further new social media restrictions at 16, the age check landscape is already shifting towards a stronger, whole-of-system approach, which is important to avoid any single point of failure.
“We want to see continued innovation from the wider tech industry to strengthen protections for children – including from operating systems and at an app store and device-level.”
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