From girls being coerced to have sex in exchange for school books to being forced into marriage, violence against girls is seen as an accepted part of being female, a report says.
The study by UK based children's charity, Plan International, interviewed 301 teenage girls and boys in Colombia, Uganda and Spain about gender roles and stereotypes.
"The horrifying testimonies of girls reveal that almost every single experience for them - be it at home, school, in public transport, or on social media - is a reminder that they are judged to be inferior to boys," said Anne-Birgitte Albrectsen, head of Plan International in a statement.
"Violence in particular has become so normalised that it is seen by many as an accepted part of being female," she said.
A third of all women experience physical or sexual violence at some point in their lives.
An estimated one in five will be a victim of rape or attempted rape, says the United Nations, and high rates of femicide and domestic abuse grip many countries.
The study attributed gender inequality to traditional misogynist attitudes that view girls as inferior and less capable than boys in all the three countries where research was done.
"This deep-seated bias which views women and girls as inferior is the greatest barrier to ending inequality," the report said.
"The key to equality is to challenge the widespread perception that girls are worth less than boys," it said.