Did you ever wonder why you can buy a pair of “cheaters” magnifying eyeglasses at the drugstore for a couple of dollars, but if you were to buy a similar pair at an optical retailer, you could pay hundreds for the frames alone?

If you did, you were on to something. The average pair of mass-produced eyeglasses costs just $2 to make, according to a 2005 report out of MIT. The retail mark-up is, to put it mildly, significant. But thankfully for cheapskates everywhere, the Internet is bringing those margins down. Way down.

Online merchants, who don’t have to pay the same overhead costs as bricks and mortar stores, can offer steep, steep discounts. Frames at GlobalEyeglasses.com start at $1 (lenses are extra, but start at under $10), while you can get a complete pair at ZenniOptical. com starting at $8. And there are literally thousands of styles from which to choose.

The biggest drawback of buying eyeglasses online has always been the inability to actually try on frames. But that is changing, too.

WarbyParker.com allows you to select up to five different frames, try them on at home for five days and send them back in prepaid shipping packaging—all for free. Most sites also have a feature that lets you upload a photo of yourself, then superimpose different glasses options on top of it. And you can always try frames on in stores, grab the make and serial number, then comparison shop online.

If you’re not happy, many sites also offer 100 percent satisfaction, money-back guarantees. And that goes even if you just don’t like the way your glasses ended up looking.

The process is easy, and most sites will walk you through, step by step. All you have to do is go into any optometrist to get your prescription, which you’ll later type into or upload to the Web site.

Just be sure to ask the doc for your pupillary distance (PD), which is used to position the optical center of your lenses. The PD is commonly not recorded on eyeglass prescriptions, but glasses can’t be made without it.

schristmann@buffnews.comnull