Sydney Women's March organiser Mindy Freiband says women are demanding equal rights in Australia and around the world.

"We are marching today in solidarity with woman all over the world against sexism, bigotry and racism," she said.

"I feel extremely proud, I think a lot of us felt hopeless after the election and this has been a huge inspiration, there's even a march in Antarctica."

Women holding banners made a strong statement at the gathering. ( ABC News: Chloe Hart )

An estimated 2,000 to 3,000 people marched through the city, and organisers said they were overwhelmed by the strong turnout.

"I am so proud of Sydney for speaking up, we don't live in an isolated world, we don't want to see nationalist agendas, we want a global agenda with women's rights high up," Dr Freiband said.

The group launched a framework to improve women's health and reproductive rights, economic participation, representing more women in positions of power and safety.

"We are concerned about Trump's regressive policies, choice of cabinet members, the empowerment hate speech gives to people in the streets and we are seeing the effects of that already," Dr Freiband said.

"We don't want people who are bigoted, racist, sexist to be emboldened by their leader in office who feels similarly."

'Nasty woman and proud' banner on display at the Sydney women's march.. ( ABC News: Chloe Hart )

Social commentator and writer Jane Caro gave a searing criticism of the incoming president.

"I'm frightened when I look at the direction that the world is heading in, I'm frightened for our planet, our climate and the whole human race. We are turning back to regressive ideas in fear of the future, that gives way to the nastiest, most disturbed, unpleasant and dangerous people in our community," she said.

"How are we still fighting for equal rights for women today — I'm sick of it, I'm over it — but we have to keep fighting for it."

At the end of the march everyone was asked to take a pledge to volunteer in the community, make politicians aware of their concerns and continue the fight for equality for women.

More than two million people are expected to attend the marches globally.

Organisers estimated between three and four thousand people attended the march. ( ABC News: Chloe Hart )

Another organiser of the Sydney march, Erin Riley, said Mr Trump is part of a larger picture.

"People are marching all around the world not just in response to Trump himself but really to all the things this year that have been a little bit concerning — the rise of this sort of populist rhetoric that is very much around divisiveness and a lot of hatred," she said.

Marches were also planned for Adelaide, Canberra and Melbourne.

In Sydney, the marchers met at Hyde Park south and headed through the city to Martin Place to the US Consular Office.

Speakers included performer Amanda Palmer, indigenous activist Jenny Munro and advocate Mariam Veiszadeh.