Tackling gender inequality and boosting women’s opportunities in the labour market could add $12tn (£7.8tn) to annual global GDP over the next decade, according to new research.

The McKinsey Global Institute has measured gender inequality across 95 countries, using 15 different indicators, including not just women’s role in the workplace, but everything from the availability of contraception to access to bank accounts.

The study found that if each country could make progress towards closing the gender gap at the pace of the best-performing economy in its local region, an extra $12tn – equivalent to the GDP of Japan, Germany and the UK combined – could be generated each year by 2025.

Women already account for about 40% of GDP in the US and western Europe; but just 17% in India and 18% in the Middle East and north Africa, according to the analysis by the research arm of the McKinsey & Company management consultancy.

Researchers believe the extra output should be attainable by making a series of reforms, including by allowing more women to join the workforce, and shifting those who are already in paid work into more productive jobs, such as out of agriculture and into manufacturing.

Closing the gender gap altogether would generate up to $28tn a year – but that looks like a distant prospect.

The authors argue that progress in allowing more women to join the workforce is unlikely to be made without significant social change. “We found virtually no countries with high gender equality in society but low gender equality in work”, they said.

In particular, they argue that progress in four areas tends to be associated with a narrower gender gap at work: education; financial and digital inclusion; legal protection of women’s rights; and the share of unpaid care work, such as cooking, cleaning and childcare.

“Realising the economic prize of gender parity requires the world to address fundamental drivers of the gap in work equality, such as education, health, connectivity, security, and the role of women in unpaid work,” the report says.

Anu Madgavkar, one of the report’s authors, who is based in Mumbai, cited Chile and Bangladesh as countries that have made progress in recent years in narrowing the gender gap.

The research also singles out policy measures that have been implemented successfully. Under Morocco’s Tayssir cash transfer programme, for example, families received payments that they could spend on education, helping to cut school dropout rates by 75%.

Madgavkar said it was also important to challenge the “myth” that persuading more women to join the workforce was bad for family life. “There are family benefits and social benefits that come from the better spending by women on food and services that children need,” she said.

She added that over the past 30 years in the US, where women’s labour participation rose rapidly, the amount of time women spend on housework has halved – partly due to labour-saving devices – while the amount of time they spend on caring for children actually increased by 30%.

Some countries have made it a central aim of government policy to tempt more women into jobs: Japan’s prime minister, Shinzō Abe, has talked about harnessing the power of “womenomics”.

But McKinsey’s research suggests that while some of the necessary changes, such as legal reforms to protect women’s property rights, would require government action, others could be driven by society and business. And women themselves are demanding faster progress.

“I would say that change is likely to come from different quarters for different reasons: women themselves in different parts of the world, and especially those who have more of a distance to travel, are becoming more vocal – we can see this in some of the younger demographics in particular,” Madgavkar said.

Narrowing the gender gap is a key theme of the sustainable development goals (SDGs) – the ambitious targets due to be signed by world leaders in New York this weekend, which will determine the priorities for overseas aid spending and anti-poverty policy over the next 15 years.

Elizabeth Stuart, of the Overseas Development Institute, said leaders’ pledge to “leave no one behind” as they work to meet the SDGs should mean tackling the barriers women face by virtue of their gender. She added: “The fact that they are talking about reaching down to the people who are the most disadvantaged: that’s really valuable.”