Q: I just moved into a new place with a couple of friends and we can't decide how to divvy up the rent. Splitting it three ways seems unfair. Is there a tech-driven solution to our problem?

SplitTheRent.bmpA: "Splitting the rent with your friends shouldn't be stressful," Jon Bittner wrote on a blog post for SplitTheRent.org published Wednesday. But it is. Hell, I don't even like going out to dinner with friends because all the fun of the evening evaporates when it's time to figure out who owes what. Same goes for the monthly rent.

Bittner, an astrophysics graduate student at Harvard, built Split the Rent, a web app that helps to take the stress out of divvying up your monthly housing costs, because "there's something both fun and funny about using a mathematical way to decide what is fair," according to his self-written About Me page. "It wasn't in response to anything specific," he wrote.

Inspiration or no, many have found Bittner's creation useful. Both Gawker's Lifehacker and AOL's DownloadSquad wrote quick posts about the app in the days after it was released. "It's a simple, yet brilliant idea, so next time you move into a new place you share with friends, perhaps put it to the test and work out whether you're paying your fair share of the rent," DownloadSquad's Samuel Gibbs wrote.

Split the Rent works with apartments or houses that have up to eight bedrooms and makes adjustments based on both the size and quality of the rooms. That is, it takes private bathrooms into consideration as well as bedrooms without windows or without doors. (Hey, you remember what communal college living was like.)

I live alone now, but I tried out the app using a house that I lived in a few years ago with three friends. I ranked three of the bedrooms as "normal" with "normal" closets. One of those bedrooms had "awesome" windows, but also "bad sound isolation" because of a flimsy wall that separated it from the living room. My bedroom was "small" and without a closet--I had to use what would have been the coat closet out in the hallway. After noting that the common spaces (kitchen, bathroom, living room, dining room) of the house were of "average" size, Split the Rent told me that I was swindled. Apparently I overpaid every month by about 47 dollars. Lesson learned: If you've got a good situation and have aleady worked out who pays what, maybe you shouldn't check out this app after all.

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