A third of children aged between eight and 17 with a social media profile have signed up with a false date of birth so they appear to be over 18, according to research.

Commissioned by Ofcom, the study by Yonder Consulting found that 77% of children in that age range have a least one social media profile, with 60% of under-12s having their own profile despite most sites having a minimum age requirement of 13.

Many online safety campaigners have called for more age verification tools to be put in place on internet platforms to better protect children from potentially harmful content.

Ofcom said it was concerned by the findings because it meant many children could be placed at greater risk of encountering age-inappropriate or harmful content online, and while many platforms have restrictions on accounts for younger users, these are steadily removed as the account holder gets older.

The study estimates that about 47% of children aged eight to 15 with a social media profile have their age set at 16 or over, while 32% of those aged between eight and 17 have it set at 18 or over.

Within those figures, it also estimates that about 23% of the youngest social media users – aged between eight and 12 – had a profile with an age set at 18 or over meaning those children could access to material aimed at adults.

The findings come as the dangers of social media to children have been pulled into sharp focus following the inquest into the death of Molly Russell, the 14-year-old who ended her life in 2017 after viewing content linked to depression, self-harm and suicide – with a coroner ruling that she died while suffering from “the negative effects of online content”.

The Government has pledged to bring the Online Safety Bill back to Parliament shortly – the landmark internet safety rules will compel platforms to protect their users, particularly children, from illegal, dangerous, and harmful content, with large fines and potential blocks on sites among the penalties for those who breach the new rules, with Ofcom as the sector’s regulator.

Some platforms, such as pornographic sites, may also be required to put age verification methods in place to prevent children from accessing their content.

It will also require the biggest platforms that are likely to be accessed by children to assess the risks of harm to youngsters who use their service, and to put in place proportionate systems and processes to mitigate and manage these risks.

An additional piece of Ofcom research found that parents and children are broadly supportive of the introduction of age assurance measures.

Mark Bunting, director for online policy at Ofcom, said: “The protection of children sits at the core of the new online safety laws, so as we prepare for our new responsibilities we’re continuing to build our evidence of children’s lived online experiences.

“Today’s research explores the triggers that may lead children to experience harm online, including the risks of signing up to a social media platform with a false older age. This can put them at greater risk of seeing potentially harmful, age-inappropriate content.

“The children and parents in the study spoke of the potential tensions between online safety concerns and the need for greater protection, with the desire for youngsters to feel socially included and to have freedom to learn how to manage risks through experience.”