Picking out an engagement ring is tricky business. Apart from learning about diamonds and jewel settings, you need to know about ring sizes. Sadly, rings are not made of elastic, “one-size fits all” material. That means you’ll need to exercise some care when it comes to picking out a correctly sized ring for your lady love. After all, when you propose to her, you don’t want to slip the ring on her finger only to have it slip right off. Or, worse yet, not be able to put it on her finger at all, and instead turn your engagement ring into a really expensive pinky ring. Embarrassing, right? Not to mention the fact that you’ll have to pay to have the ring resized, adding more cost to an already costly item.

Throwing out a wild guess about your girl’s ring size isn’t going to do you any favors. Of course, you can’t just ask your long-time companion what size ring she wears, because she’ll get suspicious. Women are clever like that, and your well-planned engagement surprise will be dead in the water thanks to your clumsy queries. But don’t despair; there are ways to surreptitiously deduce how big a ring to buy. You may have to be a little tricky when figuring out how to measure her finger without getting caught, maybe even a little devious, but the end will definitely justify the means!

Ask Her Best Friend. It doesn’t have to be a friend necessarily, just a close woman in her life. Ladies, in the course of talking about their dream weddings, will have no doubt discussed wedding rings. There’s definitely a chance that her ring size information has entered the conversation, so trying to get this valuable intelligence from one of these women may be the best way to go. The other methods are probably safer bets, but if you’re not able to pull off any of those tricks, this might be your only option to learn the size of her ring finger without getting caught. But be forewarned: when you share your plans to buy her a ring, you run the risk of it getting back to your girlfriend. If at all possible, keep all of this to yourself, and make this a one-man operation.

“While she’s sleeping, wrap a piece of string around her finger and mark the size. Any jeweler will be able to translate this into her ring size.”
– Chris Easter, editor-in-chief of GroomsAdvice.com and author of “Be The Man”

Take Her Shopping For Someone Else. If there’s a birthday coming up for a lady in your life, be it a mother, sister, or anyone else, take your girlfriend out shopping with you. Tell her that you’re thinking about getting them a nice ring, and you need her opinion. But be coy, because remember: women are smart creatures. Don’t lay it on too thick, and don’t press your luck. Just casually stop by the jewelry store and ask to see a few rings. Let her offer to model the ring for your so you can get an idea how it would look on a woman’s hand, and you’re golden.

Buy Her A Fashion Ring. Sometimes called a “right hand ring,” these little trinkets have a two-fold function. One, buying your girlfriend some jewelry is pretty much always going to net you some positive results. And two, you’re trying to measure her finger without getting caught. This doesn’t have to be an expensive ring, and in fact it shouldn’t be, because if you guess the wrong size, it won’t sting as much to have the ring re-sized or returned. Just pay close attention to what size ring you bought, and pay closer attention to how well it fits. Ask her if it ever feels loose, or if she has trouble taking it off. Also, you’ll need to consider what hand your girl favors. If she’s right handed, there’s a good chance that her left hand is going to be slightly smaller. Maybe just a half size, or maybe even a full size, but there’s probably going to be a difference. Of course, the reverse is true if she’s a lefty, so you may want to go up a bit in size from the ring you bought.

Snoop Through Her Stuff. This one is a little deceptive. In fact, if you guys don’t live together, this could be more than a little deceptive. But hey, you’re a man on a mission, right? Don’t let a little dishonesty prevent you from measuring her finger. If you’ve seen her wear a particular ring, or several rings, try to get a hold of one of them. Take it from her jewelry box or whatever she uses to keep these things safe, and take it to a jewelry store. The sales people there will be more than happy to tell you what size ring it is, especially if they think you’re going to buy a ring from them. Just return the other ring without letting her know it was taken and no one will be the wiser, you sly devil.

-Stu Moody