The same should be true when it comes to measuring our ring sizes before ordering from the best jewelry stores or hinting to a partner about gorgeous engagement rings you’ve had your eye on.

The Proper Fit

According to New York City’s Catbird, a popular fine jewelry store in Brooklyn, “Your ring should fit your finger comfortably—snug enough so that it will not fall off, but loose enough to slide over your knuckle with some resistance.”

Ring Size Guide

U.S. ring sizes follow a scale of numbers (and half numbers), typically from ring size 3 to 13.5 for adults. Women’s rings are commonly between sizes 3 and 9, while men’s rings are usually sized between 8 and 14. Those units match your finger’s width in millimeters: A ring size 3 fits a ring finger (or any finger) that is 14 millimeters across, and the sizes climb from there. The average ring size for women is between 5 and 7, but it’s always best to get an exact ring measurement before spending a lot of money—an engagement ring isn’t cheap.

Best Practices for Finding Your Size

Before you measure your ring size, there are a few pointers to keep in mind:

Consider your knuckle: If you know your knuckle is on the larger side, order half a size bigger than what your finger alone indicates, otherwise you won’t be able slide a ring into the right place.Ensure accuracy with multiple tries: Catbird’s site recommends measuring your finger three to four different times because the size fluctuates depending on temperature: It can be smaller the colder you are and more swollen if you’re overheated.

Measurement Methods

Below are three common (and easy) ways to measure your ring size at home—using string, a ring size chart, and a ring sizer—so you can get the right piece of jewelry.

Option 1: Use string or floss to measure your finger

Pro Tip: String and floss can stretch, so don’t pull them too taut. If you do, your measured ring finger size may be larger than your finger and any rings you purchase may be too big.

Option 2: Place a ring you already own on a ring size chart

Option 3: Buy your own ring sizer

For the most accurate measurement, you can purchase your own ring-measurement tool. They don’t tend to be expensive, and there are many options online. Ring-sizing tools fall into two categories: a thin measuring tape or a keyring lined with a gradient of ring sizes. Plus, you can keep these on hand to measure when you’re shopping for rings for other people in your family, too.