how to find out ring size

So, you have found the one and are finally ready to pop the question! When planning the perfect surprise engagement, you are not alone in wondering how to find your partner's engagement ring size without them knowing. Luckily, we have spoken to our jewelry experts and uncovered all the different ways to subtly measure your partner's ring size!

Measure Your Ring Size with Our Free Ring Sizer Tape Measure

We will happily send you a complimentary plastic ring sizer so you can easily find your perfect ring size at home.

How to Measure Your Ring Size with Our Free Ring Size Conversion Chart

If you would like to measure your ring size with a piece of paper at home, print out our ring size conversion chart . Before you print the guide make sure the page scaling is set to "none" on your print dialog box.
Take the ring size chart and place your ring over the circle that aligns with the inside edge of your ring. Make sure you are using a ring that fits the same finger (and hand) as the ring you want to purchase.

How to Measure Your Ring Size with Our Free Printable Guide

Alternatively, you can print our ring size guide at home to measure your ring size. Before you print the ring size guide make sure the page scaling is set to "none" on your print dialog box.
Cut out the ring sizer and then cut a slot on the dotted line. Wrap the ring sizer tightly around the widest part of the intended finger with the numbers showing toward you. Insert the arrow-end through the slot you cut. Your ring size is the number that lines up with the slot.

How to Measure Ring Size Using String, Paper, and a Ruler

Step 1: Cut a piece of non-stretchy string (or a strip of paper) and wrap it around the base of your partner's left finger.
Step 2:Identify the point where the end meets the string and make a pen mark.
Step 3: Lay the string flat and measure the length of the mark you made in millimeters (mm).
Sept 4: Compare the measurement to our ring size chart to find the closest ring size.

6 Ways to Measure Ring Size Without Your Partner Knowing

Be Subtle

If you are set on a surprise proposal but want to have the correct measurement by getting the information directly from the source, you must acquire the information in a very subtle way. For example, if you are proposing to your girlfriend, you can pretend you are going to buy a ring for your mom, sister, grandma, or even yourself. Just make sure this pretend recipient is someone whose finger is similar in size to your partner's left ring finger. Casually ask what your partner's ring size is for reference. If you really want to step up the ruse, purchase an inexpensive ring and have your partner try it on to see if it is the perfect fit. And afterward you can give that decoy ring to your mom, sister, or grandma to appease your guilty conscience!

Ask Friends

One of the best ways to find out your partner's ring size is to ask one of their friends. If the friend does not know right away, he or she can be the one to ask (nonchalantly). One step better, ask the friend to take your partner engagement ring shopping "for fun." That way your partner will get professionally sized and maybe drop a hint about what styles they like!

Borrow a Ring

Another strategy is to borrow one of your partner's rings for a day. You do need to be careful with this tactic because it might backfire. Make sure you borrow a ring that they won't notice is missing and that's similar in size to your partner's left ring finger.

Leave a Trace

If you are terrified of losing one of your partner's rings, try this method instead. Take one of their rings and place it on a piece of paper. Draw a circle on the inside and outside of the ring. Do this several times to make sure your ring traces look consistent and can indicate the correct ring size. A Brilliant Earth Jewelry Specialist can typically figure out the measurement of the inner diameter from your sketch! Even better, use our ring size conversion chart for additional tracing accuracy!

Enlist an Engaged Friend

If you and your partner are spending time together with someone who is engaged, secretly ask that engaged friend to let your partner try on their engagement ring. This will put you in a ballpark size range to start out with. You can also use this as an opportunity to ask your partner what they thought of the friend's engagement ring (in private) to try to do a little sleuthing as to what style of ring your partner would like .

Compare Fingers

This method is a little less accurate, but if you are desperate, go ahead and try it out! When you are holding your partner's hand, see if their ring finger is similar in size to one of your fingers. For example, their left ring finger might be as big as your pinky. Again, this strategy will not be as accurate, but the more measurement information a professional jeweler has about your partner's ring size the better!

6 Ring Size Tips and Facts

Our dominant hand tends to be slightly bigger, so make sure you are measuring your partner's left ring finger.
If you haven't gotten your partner's exact measurement, err on the larger size so the ring is sure to slip over the knuckle of your partner's ring finger when you propose.
The most common women's ring size is 6 to 6.5.
The most common men's ring size is 10.
Wider bands have a tighter fit than thinner bands, so if you borrow a ring to measure, try to make sure that it is the same width as the ring you plan on purchasing.
Finger size changes a little throughout the day because of temperature, activities, etc. When warm, fingers tend to expand slightly. When cold, fingers tend to shrink. Most people find they have puffier fingers in the morning, but that their fingers shrink to their normal size during the day.

Ring Sizing FAQs

Do I measure my ring in mm or cm?

In the United Stated and Canada, ring size is most commonly measured by the inner diameter of the ring in millimeters. At Brilliant Earth, we also measure in millimeters and convert the measurement to the nearest half ring size.

What is a comfort fit and how do I measure for it?

The shape of the ring's inside edge is what determines if it is a comfort fit ring or a standard fit ring. Standard fit rings have a flat inside edge that fits snuggly against your finger. Comfort fit styles, like our Petite Comfort Fit Ring , have a beveled or curved inside edge that allows the ring to more easily slide on and off your finger. Comfort fit rings are ideal for those with wide knuckles or hands that easily swell.

What if I order the wrong size ring?

Brilliant Earth offers complimentary ring resizing within the first 60 days for most rings. This is to ensure customers get the perfect fit. We also offer complimentary 30 day returns. If for any reason you are not satisfied with your purchase, you can return it within 30 days for an exchange or full refund.

What happens when my ring is resized?

When a ring is resized, the jeweler will cut through the back of the band and either remove or add metal to change the size of the ring. If your ring needs to be resized by two or more sizes the best course of action is to return the ring and repurchase the right size. An extreme resize can compromise the structure of the ring.

Can all rings be resized?

While most ring types can be resized, eternity ring styles cannot be resized due to their design. If resizing is a possible concern, it is best to choose an engagement ring with a metal back, like a solitaire setting . You can also consult with a Brilliant Earth Jewelry Specialist to ensure that your ring setting is eligible for resizing.

How do I measure ring size using a ring?

You can find the measurement of a ring you already have by taking a ruler and measuring straight across the center from edge to edge. Using the ruler, document the diameter in millimeters. Take that number times 3.14 to find the circumference of your ring. Compare the circumference to our ring sizing chart to find your size.

Can I measure my ring size at home?

The best way to find your ring size at home is by ordering a free Brilliant Earth plastic ring sizer . If you need to find your ring size on the spot, the next most accurate approach is using the string and ruler method listed above.

What if I can't figure out the size?

If you can't figure out your partner's ring size or don't want to risk being wrong, consider a temporary setting to propose with. Brilliant Earth offers an 18K White Gold 2mm Comfort Fit Ring as a temporary setting. With this option you have 60 days to propose, have your partner sized, and return the ring. Once you have your partner's perfect fit, Brilliant Earth will set your diamond in your chosen setting. This method allows your partner to see the diamond you chose, but there isn't the risk of having to resize the actual setting. This method is also a great option for those who don't know whether to purchase an engagement ring before or after proposing. Please live chat or contact us if you are considering this option.

Final Thoughts

Something to keep in mind is that the most accurate way to find the perfect ring fit is to have your partner's ring finger sized by a professional jeweler. Using one or several of the methods above will result in a close approximation, but there is always the risk that your measurement will be slightly off. For custom engagement rings we highly recommend visiting a jeweler to get an accurate size because custom pieces are final sale and may not be able to be resized in the future.

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