Birth weight among social mobility checks - Nick Clegg
The government is to publish an annual "snapshot" of social mobility, by measuring information such as educational achievement, access to professions and birth weights.
Deputy Prime Minister Nick Clegg said being able to advance at work and in learning was a "vital ingredient" of the UK's economic success.
Wasted talent was a "crime" which hurt society, he added.
But Labour said life chances were going "backwards" under the coalition.
Campaigners claim that social mobility in the UK has reduced since the 1960s. The government has commissioned former Labour Health Secretary Alan Milburn to investigate the issue.
At a conference organised by the Sutton Trust, which promotes educational opportunities for young people from underprivileged backgrounds, Mr Clegg called for "a more dynamic society: one where what matters most is the person you become, not the person you were born".
He dismissed as a "myth" the idea that social mobility can increase only during times of economic prosperity, saying: "I strongly believe that opening up our society is a vital ingredient in our future productivity. Wasted talent is always a moral crime, but it is increasingly an economic crime too.
"The Sutton Trust's own work has suggested that boosting poor educational attainment up to the UK average would increase GDP by £140bn by 2050, and increase long-run trend growth by 0.4 percentage points. Social mobility is a long-term growth strategy."
He announced the annual publication of a set of 17 indicators to monitor "how well the government is doing in making society fairer".
These include the proportion of children under five on free school meals achieving a "good level of development" compared with other children, attainment at age 16 of those eligible for free school meals and higher education enrolment by social background.
Birth weight will also be measured. Babies from disadvantaged backgrounds are more likely to be underweight and this has been associated with "a wide range of poor educational and health outcomes later in life", the government says.
It adds that this will be the first time such information has been published by any government in the world.
Mr Clegg argued that life chances could not be evened out simply by reducing inequality, pointing to Australia and Canada as examples of countries with a similar gap between the rich and the poor as the UK but much better levels of social mobility.
He described suggestions that the government was trying to "socially engineer" as "nonsense".
Mr Clegg, who attended a top public school, added: "I know some people will say I should keep quiet about social mobility, that my birth, my education, and my opportunities mean I have no right to speak up. I couldn't disagree more.
"If people like me who have benefited from the system don't speak up, we will never get anywhere."
But Labour's deputy leader Harriet Harman said Mr Clegg would have more credibility on the issue if the government wasn't pursuing policies that damage the prospects of young people and increase inequality.
She said: "He's part of a Tory-led government which is closing children's centres and has scrapped the Education Maintenance Allowance and the Future Jobs Fund, while more than a million young people are out of work.
"Cutting taxes for millionaires while millions pay more makes inequality worse, not better," she added.