A research fellow at Canberra University, Jenny Chesters, analysed data from the Household Income and Labour Dynamics in Australia project and found private school students were no more likely to get a full-time job than public school students.

And while private schools students were more likely to attend one of Australia's most prestigious universities, even this did not lead to a higher income the research found. 

"If a parent wants to pay to send their child to a private school, I don't have a problem with that but they should know that if they think paying for an education is an investment and you will get a monetary return on it, you probably won't," she said.

Dr Chesters looked at the data for 2168 people aged 24 to 35 in 2012. About 70 per cent went to government schools, 17 per cent to Catholic schools and 13.5 per cent to independent schools.

The data showed that while students from Catholic or independent schools were more likely to have completed year 12, public school students were not disadvantaged once it came to securing a well-paid job after university.

Dr Chesters said the "massive growth" in the number of private schools since the 1990s could be "diluting" the perceived advantages that were once attached to private schooling. 

"There has been an explosion in independent schools since John Howard changed the funding formula so, if you are aged 25 to 34, an independent school is a very different place than it was if you are 45," Dr Chester said.

Career development expert Martin Smith insists a person's high school is a "very, very negligible part of the recruitment process".

"Recruitment processes these days are much more sophisticated and much more objective than they may have been 20 years ago," Mr Martin said.

Once students are accepted into university, he said, the playing field is more or less level.

"Students who have had to strive and struggle to get to university are often very motivated," he said.

He acknowledged some people could be advantaged by their networks and personal relationships.

"But, then again, those who don't have those same networks may be more proactive and enthusiastic in the way they chase down their opportunities," he said.

But Tim Hawkes, the headmaster of The King's School, where school fees for senior students are more than $30,000 a year, said a quality education was about producing a good person, not gaining a prestigious job.

"When parents come to King's looking to enrol their sons, they are looking for a school that will discover the true potential in their sons," Dr Hawkes said.

"They are looking for teachers that will inspire their sons and create within them a sense of wonder. They are looking for a place that reinforces good values, they are looking for the Christian ethos and they are looking for an all-round education where conscious attention is paid to the intellectual, social, emotional, physical and spiritual development of their son."

Katie Paull graduated from Colo High School, a comprehensive public school in the Hawkesbury region, and studied law at Macquarie University, before securing a competitive clerkship at one of Sydney's top-tier law firms.

She doubts her high school had any bearing on employer's decision to hire her and said the question never even came up through the recruitment process.

"My experience has been that there's more focus on where you went to university rather than where you went to high school," the 25-year-old said.

"We had fantastic teachers at my public school and I think I received the best education I could have received. I've got no regrets or hesitations about where I went to school and I'm very proud of the fact that I'm a public school alumni."