More than one in five women have experienced online harassment or abuse, according to research by Amnesty International surveying more than 4,000 women.

The vast majority of this harassment happens on social media sites, according to the report.

Almost half of the victims said the abuse or harassment was sexist or misogynistic in nature, and a quarter had received physical or sexual threats.

A majority of the harassment - almost 60 percent - was racist, sexist, homophobic or transphobic, the poll showed.

"The internet can be a frightening and toxic place for women. It's no secret that misogyny and abuse are thriving on social media platforms, but this poll shows just how damaging the consequences of online abuse are for the women who are targeted," said Azmina Dhrodia, Amnesty's researcher on technology and human rights.

Harassment can leave lasting damage, noted the representative survey, conducted in eight Western countries.

Of those who had been victims of harassment, 41 percent felt less secure in their daily lives because of the abuse they had experienced, and one in four feared for the safety of their families.

A vast majority of women also said they were apprehensive about using the internet after being targeted.

Besides sexist, racist or homophobic abuse, 17 percent of the victims said they had identifying personal details or private photos shared online.

"This is not something that goes away when you log off. Imagine getting death threats or rape threats when you open an app or living in fear of sexual and private photos being shared online without your consent," Dhrodia said.

Although social media companies have all touted efforts to battle harassment and abuse, some say this does not go far enough. Both Facebook and Twitter, two of the most popular social media sites, are not handling abuse in a satisfactory manner, according to the surveyed women.

"Social media companies have a responsibility to respect human rights, including the right to freedom of expression. They need to ensure that women using their platforms are able to do so freely and without fear," Dhrodia said.

Another issue is the lack of policies and laws in place to protect victims, the Amnesty report noted.

The organisation has called on governments to work towards proper legal frameworks to curb online harassment, without infringing upon the right to free speech.