The number of people seeking help about viewing child sex abuse images online has more than doubled in the past year.
The Lucy Faithfull Foundation said 94,342 people in the UK contacted its Stop It Now! helpline by phone or visited the website in 2019.
This was more than double the 43,019 who contacted the charity in the previous year.
Users included potential offenders as well as people who are worried about someone close to them.
Last month, a separate charity revealed it had dealt with a record number of online child sexual abuse reports in 2019.
According to the National Crime Agency (NCA), about 80,000 people in the UK are classed as posing a sexual threat to children.
In its strategic assessment in 2019, the NCA said there were about 140,000 UK users registered on the worst child sexual abuse sites on the dark web worldwide.
Chief constable Simon Bailey, the National Police Chiefs' Council lead on child protection, said: "Accessing these images is not a victimless crime and viewing them creates more demand for these appalling offences.
"We are arresting more offenders than ever before - at least 500 people a month - and our tools for investigating and tracking down those responsible are the best they have ever been.
"We are committed to targeting the perpetrators of these crimes and bringing them to justice. The consequences of being caught are huge and include losing your job, your family life, being imprisoned and registered as a sex offender.
"Anyone who is having inappropriate thoughts about children should seek help from Stop It Now!, otherwise they should expect a visit from police officers."
The Lucy Faithfull Foundation has launched two films that show men who look at sexual images of children under the age of 18 being caught by a loved one.
Donald Findlater, director of the Stop It Now! Helpline, said: "Tens of thousands of men in the UK are viewing and sharing sexual images of under 18s - these men are our friends, family, neighbours and colleagues.
"Most are adults, but a significant proportion are teenagers. Many of these men started viewing this illegal material as part of their adult pornography habit, somehow not noticing or perhaps caring that these were images of children being abused.
"Some don't know the law and need it spelling out. A few are struggling with a long-standing sexual interest in children and think that looking at 'only pictures' is a way of containing that interest.
"Whoever they are, they need to know this behaviour is illegal, that children are harmed by it, that serious consequences await those involved in it, but that our helpline and website give anonymous and confidential support and advice to stop and stay stopped."