How to Find Your Ring Size Before You Order Online

A ring that doesn't fit is one of the most common reasons jewellery goes back to the seller, and some rings can't go back at all. Resized, engraved and made-to-order rings are often final sale. A few minutes of careful measuring before you order saves a lot of hassle.

Measure the right finger, at the right time

• Measure the finger the ring will be worn on. Fingers on the same hand can differ by a full size or more, and your dominant hand is often slightly larger.
• Measure when your hands are warm and relaxed. Fingers shrink in the cold and swell with heat, salt, and after exercise, so measuring first thing in the morning or after a cold walk can give a size that is too small.
• Measure more than once, on different days or at different times of day, and go with the size that comes up most often.

Three ways to measure at home

1. A ring that already fits. If you own a ring that sits comfortably on the same finger, measure its inside diameter across the widest point with a ruler (in millimetres), or lay it against the seller's printable size chart if they offer one. Use a ring of a similar width to the one you plan to buy.
2. A ring sizer. Plastic adjustable sizers or sets of sizing rings are inexpensive and the most reliable home method. Some jewellers post a free sizer on request.
3. A strip of paper or string. Wrap it around the base of the finger, mark where it overlaps, and measure the length in millimetres. This gives the circumference. It is the least accurate method, because paper stretches and string slips, so treat it as a rough starting point.

Whichever you use, check that the result can slide over your knuckle with a little resistance and still sits snugly at the base of the finger.

Sizing systems: US, UK and EU

Sellers use different systems, and the same finger has a different number or letter in each.

• US and Canada use numbers, such as 6 or 7½.
• UK and Australia use letters, such as L½ or N½.
• EU and many other countries often give the inside circumference in millimetres.

These approximate matches are a useful sanity check, not a substitute for the seller's own chart:

Always use the conversion chart on the seller's own page. Brands round differently, and some use half sizes where others only list whole ones.

What changes the size you need

• Wide bands fit more tightly than thin ones. For a band wider than about 6 mm, many people go up half a size or more.
• Large knuckles. If your knuckle is much bigger than the base of your finger, choose a size that passes the knuckle, or ask whether the ring can be adjusted.
• Between sizes. If you are between two sizes, the larger is often more comfortable for a wide band and the smaller for a thin one.
• Materials. Rings made of metals that are hard to resize, such as some tungsten, titanium or ceramic designs, may not be resizable at all, so get the size right first.

Questions to ask before you buy

• Is resizing free, paid or not possible? Some stores offer one free resize or exchange, and others don't.
• Which size system does the listing use, and does it give a measurement in millimetres?
• Is the ring made to order or engraved? If so, returns are likely limited. Read the returns policy before paying, as covered in our guide to refunds and chargebacks.
• How long is the returns window, and who pays return postage?

For the metals, hallmarks and quality marks behind the product description, see our guide to buying jewellery online. If you are buying from overseas, check customs and duty rules in our international shipping guide.