Thinking about college costs? Check out this comparison tool

Money-filled Mason jar labeled

If you're thinking about saving for your kid's college bills, a new college comparison tool might give you a taste of what's ahead.

The Consumer Financial Protection Bureau, the new federal agency that's designed to help protect and educate consumers, just released the beta version of the Paying for College Cost Comparison Worksheet.

The agency calls the worksheet a "thought starter" and asks the public to give it a test-drive and tell its designers how to improve it.

So that's what I did.

The first screen asks you to type in the names of three colleges or universities you'd like to compare.

Our kid is still in elementary school, so I don't have a financial aid offer in hand.

Instead, I compared the three colleges to which I applied back when I was a high school senior: Oberlin College in Oberlin, Ohio; Bates College in Lewiston, Maine; and Carleton College in Northfield, Minn.

The site then accessed current information about each college's sticker price -- broken down into tuition, books and fees, room and board, and estimated personal costs -- and the average amount of grants and scholarships each gives.

Subtracting one from the other, the site shows you how much you'll need to borrow to pay the difference between the two.

Then the site figures your estimated student loan debt after graduation, broken down into monthly payments over 10 years.

It tells you how many $50 textbooks you could buy for that monthly payment and indicates whether that debt load is low, medium or high compared with debt taken on by other students.

You can fiddle with the numbers by clicking the "enter financial aid" button and telling the site how much money you and your family can contribute, what other scholarships and grants you have, what federal loans you can get, and what private loans you may be willing to shoulder.

The first thing the site told me is that I have astonishingly expensive tastes in colleges.

Back when I was a freshman, these colleges all had comprehensive fees of about $16,000 a year. Now the price tags hover around $56,000 a year.

The site underlines my deluxe ideas about higher education by offering me a comparison to private schools in general -- around $42,000 a year -- and to average in-state public school tuitions -- about $21,000.

Then I played with the numbers for Carleton College, the school I actually attended.

When I did this, Carleton's box expanded to let me fill in funding categories. It also told me that Carleton has high retention and graduation rates. It's nice to know that I'll probably get a degree to go with my debt.

The site also tells me that student loan default rate data are unavailable for Carleton.

It would be nice to see a low number here, as it would suggest that graduates get jobs that pay well enough to cover their monthly loan payments.

(The U.S. Department of Education's College Navigator does provide some default data for Carleton and offers more information on college costs in general than does the CFPB worksheet. It does not, however, appear to allow you to calculate your cost after accounting for financial aid, like the CFPB worksheet does.)

Overall, the CFPB site does a fine job of organizing my math in one place. I could have worked all this out on my own, but it's nice to have a website do some of the driving.

That said, the site isn't flawless.

Its biggest limitation is that it can predict debt load for two kinds of students: imaginary and already accepted.

It can't predict debt load for specific students who are interested but not admitted, and it may deter some of those students from applying to more expensive schools.

Here's why.

The numbers it gives are simple averages. Carleton gives about $29,000 in aid to the average student, a number that includes students who pay full freight, students who pay nothing at all and everyone in between.

Your financial situation might mean that you get a free ride or something very close to it, but the average discounted price of $27,000 might scare you off before you ever apply.

By the same token, you can't rely on the site to compare your actual, likely aid offers from two different colleges.

For instance, this program indicates that Bates offers an average of just more than $37,000 in grants and scholarships. Carleton's average is substantially less, at about $29,000.

Yet when I applied, Carleton gave me substantial grants and scholarships while Bates gave me nothing at all.

Determining likely financial aid is a much more complex process, and I understand the Consumer Financial Protection Bureau isn't trying to do that here.

The stated goal, in fact, "is to give students and their families an easy-to-understand view of how their decisions today impact your debt burden after graduation," according to the website.

That being said, the site would benefit from language reminding users that their mileage may vary.

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