US student debt is accelerating towards a new, $2 trillion milestone — a 30 percent surge within the next 36 months — according to an analysis.

And as the debt climbs rapidly higher toward that record number, up from $1.54 trillion, according to the Federal Reserve Bank of New York earlier this year, the return on investment for college grads is shrinking just as fast, analysts warn.

The monumental student debt bill, growing by nearly $30 billion each quarter, is racing toward $2 trillion by as early as 2021 — less than a decade after street protests erupted over it surpassing $1 trillion in 2012.

“As long as the overall population continues to grow and as college tuition costs continue to rise, US student debt will keep growing,” said Vince Passione, founder and chief executive officer of LendKey, a digital lending platform facilitating student loans from credit unions and community banks.

“Since 2010 we’ve seen an abundance of federal loans being made widely available to students,” said Passione, the son of a New York City police officer, who graduated from college in 1983 and initially took a second job to quickly pay off his $20,000 in student loans.

“Anytime you make the free flow of credit with easy access to credit,” Passione added, “it inflates the asset class [rising tuition costs]. Look at the Great Recession: mortgages were made readily available, and you see what happened.”

In the last decade alone, student debt has surged by nearly 60 percent. And the latest forecast will only up the ante and financial pain. At this predicted growth rate, millions more are likely joining today’s cadre of 44 million American student-loan borrowers, with the average undergrad in 2017 owing $39,400, analysts say. On the extreme end of the spectrum, 101 US grads owe a minimum of $1 million each on loans, according to Department of Education data. “A couple of my friends in medical school owe about $200,000 each — that’s scary,” one recent grad, who declined to be named, told The Post.

One analyst expects a disaster when the bubble finally pops.

“This really is a frightening bubble which will have a negative impact on our whole economy and on student loan borrowers,” said Richard Farrington, a student loan debt expert at The College Investor, who calculates that total student loan debt of $1.54 trillion could cross the $2 trillion mark within the next three years.

“We read all the stats about millennials delaying big purchases and spending — and these stats have a lot to do with today’s student loan debt.”

Millions of student borrowers are already in default. And many young grads are staring at a lifetime of payments that will hamper their ability to buy homes and raise families.

After peaking at 69 percent at the top of the housing bubble in 2005, homeownership rates have fallen sharply in the US. And among millennials, the drop is especially acute.