With the cost of college rising rapidly enough to outpace inflation, many parents and would-be students find themselves wondering whether it pays to take on the expense. If you're not sure whether college is worth it, consider this: The national average yearly salary for a college graduate with a bachelor's degree is $57,026, compared to $34,197 for someone with just a high school diploma. Before you write off college as too expensive, consider the benefits of a degree, as well as some lower-cost alternatives to reduce the amount of debt you rack up in the process.

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The costs keep climbing

So just how much does college cost these days? According to the most recent estimate, these were the average costs of attending college for the 2015-2016 school year, including room and board:

  • $19,548 for public four-year in-state school
  • $34,031 for a public four-year out-of-state school
  • $43,921 for a private four-year non-profit school

Keep in mind that room and board -- a sometimes unnecessary expense -- adds about $10,000 a year to the cost of college. But even if we take room and board out of the equation, it still costs close to $10,000 a year to attend a public in-state school, and over $32,000 a year to attend a private college. That's a lot of money to spend for the promise of a higher salary.

Is college worth the cost?

If you're not convinced that college is worth the price tag it commands, this handy calculator can help you run the numbers and arrive at a decision:

 

* Calculator is for estimation purposes only, and is not financial planning or advice. As with any tool, it is only as accurate as the assumptions it makes and the data it has, and should not be relied on as a substitute for a financial advisor or a tax professional.

If you use the average national salaries for college graduates versus high school graduates, you'll see that, over the course of a 40-year career, you may earn as much as $1.7 million more with a bachelor's degree than you would with just a high school diploma.

Assuming a 3% annual salary increase, if you start out at $57,026, your lifetime earnings will total $4.3 million with a bachelor's degree, whereas you'll wind up with $2.6 million in lifetime earnings without one. So let's say you need to spend $19,548 a year to get your bachelor's degree at a public four-year college. At the end of the day, you're dishing out $78,192 to earn $1.7 million more over the course of your lifetime. That sounds like a no-brainer -- but don't forget two variables you can't ignore: student loans and the opportunity cost of an education.

How much will your debt really cost you?

Any time you borrow money to pay for something, whether it's a car, a house, or a college degree, you'll wind up spending more to repay that debt, thanks to the interest charges you'll incur. So let's see how much a four-year degree at a public college might cost if you need to borrow that $78,192 in full.

Assuming it takes you 10 years to repay your loans at 5% interest, you'll wind up spending a total of $99,522 to get your degree. Now, that's still a lot less than the $1.7 million you'd be missing out on by not going to college, but before you can decide whether it's really worth it, we still have one more set of numbers to crunch.

Let's say that, instead of borrowing $78,192 and graduating with a monthly loan payment of $829, you invest that $829 a month and generate an average annual 8% return -- which is doable when you invest in stocks -- over the course of 10 years. After a decade, you'll have $144,114. Now let's say you leave that money alone and keep it invested for retirement for another 35 years. Even if you don't add another dime, you'll wind up with $2.1 million by the time you're ready to retire -- which more than makes up for the $1.7 million in salary you'd be missing out on.

Of course, it's not really that simple. In our scenario, we're assuming that you'd be able to take the $829 you would've otherwise spent on a loan and invest it for retirement. In reality, if you're earning a lower salary because you never went to college, you may not have that amount to save. That's why your takeaway shouldn't be that college is not worth the money. Rather, the lesson here is that attending college is a major financial decision that shouldn't be taken lightly.

Also keep in mind that there are ways to get a degree without spending a fortune. If you can live at home during college, then you could shave about $40,000 off your total cost. You might also consider working part-time while you're at school to minimize your loans and the interest payments that inevitably go along with them.

Finally, think long and hard about whether you're actually likely to earn a higher salary by getting a degree. Though a bachelor's degree can help you get ahead in certain professions, there's no guarantee that you'll make more or less money by going or not going to college. There are numerous factors that will come together to determine how much you end up earning in a lifetime, and college is by no means the only one.