More than one in three experienced sexual harassment, and campaigners believe this behaviour against girls and women should be criminalised.
Angela Salt, chief executive of Girlguiding – the charity that commissioned the research – said the abuse is having a “devastating impact”.
With 16 per cent of girls and women facing pressure to share naked pictures of themselves, Girlguiding found nearly all of the 13-to-15-year-old girls who experienced these pressures had negative emotions, such as depression, anxiety, anger and fear.
Girls with disabilities experience the most bullying, sexist comments, and pressure to share pictures of themselves, compared to those without a disability.
Out of the 1,002 girls and young women polled, only 15 per cent believe social media is a safe place for them.
Speaking to The Guardian, Eva, 11, said she was bullied over Facebook Messenger aged nine, when school friends accused her of carrying out a sexual act with boys.
She said: “I didn’t understand. I was really confused by what they were saying.”
Eva’s mother Emma said she felt “physically sick” when she found the messages.
Ministers are being called upon to make online safety legislation stricter, with MPs on the digital, culture, media and sport committee criticising a draft bill as not “clear and robust enough to tackle the various types of illegal and harmful content on user-to-user and search services”.
Salt said: “Girls and young women should be able to use the internet freely, safely and without fear. Sadly, our research highlights that there is still a long way to go before this is reality, which is why we are calling on the government to ensure violence against girls and women online and its devastating impact is recognised and included within the online safety bill.”
MPs want the bill to address content which is technically legal – including types of online violence against women and girls such as tech-enabled “nudifying” of women and “deepfake” pornography, either through primary legislation, or as types of harmful content covered by the duties of care of service providers.
This week, it was reported that cyber-flashing – including the sending of “dick pics” – could be criminalised, through inclusion in the Sexual Offences Act 2003, which will lead to perpetrators being included in the sex offenders’ register in England and Wales.
In Scotland, cyber-flashing is already illegal.