Seven in 10 children aged between nine and 13 say they have been exposed to harmful experiences or content online, according to new research.
Figures also show that a fifth of children in the same age group have been contacted by a stranger.
The data, released on Thursday by charity Internet Matters in partnership with Opinium, found 17% of nine to 13-year-olds have seen content that promotes online stunts or challenges.
Other harmful online experiences reported by children in this age group include coming across hate speech (13%), coming across mis/disinformation (15%) and one in ten have seen violent content or content that promotes violence.
The children were also reported to be spending 23.2 hours online each week, two hours more than their parents realise.
Internet Matters warned parents were “underestimating” the amount of time their children spend online, “which unknowingly may further expose and leave them open to further risks”.
The study is based on research conducted between May and June among 1,000 children aged nine to 17, 2,000 parents of children aged three to 17 and a further 1,000 parents of children aged five to 17.
The group said it chose to research this age group as it is a time “where many may be getting their first smartphone and have increased access to the digital world”.
About three-quarters (74%) of parents surveyed said they do not use browser safe search settings or filters, potentially leaving children just a few clicks away from accessing harmful content – even if they are not intentionally searching for it.
Meanwhile, about two-thirds (67%) of parents do not use parental controls on their home broadband.
In a bid to help parents, Internet Matters has launched a Government-supported “ABC online safety checklist” which covers a series of actions for parents to take.
The ABC checklist is:
Activate parental controls – Use the controls and tools available from broadband providers, online platforms and apps to install safe search settings, block inappropriate content and prevent contact from strangers.
Balance screen time – Agree a good balance for your children’s screen time, taking education and leisure content into account. Explore whether your child’s screen time is more passive than active and consider setting limits for the total hours spent online each day.
Check and chat – Check which apps your children are using and the relevant age limits for each platform. Talk regularly about online safety and what they might come across – it might seem daunting , but your children will benefit. Reassure them that you can work together to manage any risks and make their online experiences as positive as possible.
Baroness Jones, minister for online safety, said: “Creating a safer online world is vital for children and the health of our wider society.
“The Online Safety Act will introduce major obligations to protect children from harmful content online and we are committed to getting these protections in place as quickly as possible.
“It is also important parents are supported to make informed choices about their children’s social media use and resources like Internet Matters’ online safety checklist will help parents get the online balance right for their families.”
Rachel Huggins, co-chief executive of Internet Matters, said: “With technology constantly evolving, there’s so much to think about when it comes to online safety that parents and carers are quite simply overwhelmed. We want to help them protect their children online while still enjoying all the benefits the internet has to offer.
“Thinking about online safety comes on top of all the jobs parents already have, so the ABC checklist gives them a place to start with some actionable tasks that can make a real difference and give them added peace of mind.”
