The two numbers may not seem similar, but Magnify Money has studied how medians of the two look in a larger context.

A home mortgage used to be the biggest debt you might ever take on. Yet student loans, as they get bigger, are starting to elbow mortgages aside as the bigger amount, according to Magnify Money , a division of Lending Tree that provides content, tools and reviews.

The cheaper your home, the more comparable it's going to be to your student loan balance.

"Averages tell you the range," said Kali McFadden, senior research analyst for MagnifyMoney and LendingTree. "But the median gives you a better sense of what's happening in the community."

For borrowers in cities where home prices are on the lower side, increasing student loan balances mean the two numbers are moving closer together.

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Mortgage debt is lower on these cheaper homes, and the holder of the mortgage could be the parents of a student, not the actual student, McFadden says. "They could be 20 years into the mortgage, and also paying higher interest on the federal loan than a student would pay," she said.

The report uses borrower data from the 50 biggest metropolitan areas to identify cities where borrowers' student loans are more likely to rival — or even surpass — their mortgages.

"Most people do not owe more in student loans than in mortgage debt," McFadden said. The numbers factor in some people, mostly in professional fields, who do have hundreds of thousands of dollars in outstanding student loans.