How to size an engagement ring

17th March 2023

Your engagement ring is a constant reminder of your commitment to one another, so ensure an accurate measurement before your big day. Nothing feels worse than losing a valuable item if it’s too loose on your finger or having a ring that’s too tight and uncomfortable. We'll walk you through some steps to discover your size — so your ring is the perfect fit.

Things to keep in mind before sizing a ring

Throughout the day, your ring size may change depending on several things. For instance, warm weather can make your fingers swell up, while they tend to get slimmer in colder weather. Ideally, you should avoid taking your measurements when you are too hot or cold. Instead, measure your ring when you have a regular body temperature to get the most accurate size.

As a general rule, it’s a good idea to buy an engagement ring in a slightly larger size compared to a smaller size that won’t fit. You can always wear a ring stopper and resize it to make it smaller later on, whereas a too-small size may cause more significant discomfort.

Reading a ring size chart

When shopping for an engagement ring, choosing a size that comfortably fits your fiance's finger is essential. A common mistake is to assume that all ring sizes are the same, but there can be significant variation between different countries and even between other jewellers. As a result, consult a size chart before making your purchase, so you know if you need to make a conversion.

Unlike American sizing, which is given in numbers, UK sizes are given in letters. Sizes can range between F and Z+4, with half sizes for those in between. Typically, size charts include the inside diameter and circumference of the ring measured in millimetres.


How to measure your own finger

Can you measure a ring at home? Most definitely. At Austen & Blake, we offer a free ring sizer that can give you a relatively accurate estimate of your engagement ring size. You’ll need access to a printer, some A4 paper and an existing ring that fits the intended finger for this size guide.

To set up your printer correctly, ensure that your page scaling is accurate. Once you’ve printed your measuring sheet, check that the left bar measures precisely 3 centimetres. Next, grab the ring you want to measure and match the inside of the ring to one of the dotted circles that are closest in size.

Although this can be an excellent way to check your ring size, you should keep in mind that sizing can vary based on the thickness of your band and whether you’ve measured yourself accurately. If you’re unsure of your ring size, you can always ask a jewellery professional to measure your finger on your behalf.

How to get someone's ring size

Couples often face a dilemma: ‘how do they know a ring size before proposing?’. There are many things to consider when it comes to a surprise proposal besides types of rings. You want to ensure you have the perfect ring, setting and, of course, that the ring is the right size. Here are a few tips on how to figure out your partner's engagement and wedding ring size before you pop the question:

  • Ask their friends or family — If you're close with your partner's friends or family, they may be able to give you a clue as to what size ring your partner wears. Just be careful not to let slip that you're planning to propose!
  • Borrow one (or more) of their rings — This is a great way to get an accurate measurement. Make sure you return the ring before your partner notices it's missing! For bonus points, try borrowing several rings and trace the internal diameter and external circumference of each one with a pencil and paper. Repeat this process several times for maximum accuracy.

Resizing your engagement ring

Fortunately, most rings can be resized relatively easily by a professional jeweller. The resizing process typically involves adding or removing metal from the band, which generally takes a few days to complete.

While sizing up or down by a couple of sizes is usually no problem, extreme resizing can sometimes weaken the ring's structure and affect its overall appearance. As such, it's always best to consult with a jeweller before making any drastic changes to your engagement ring.

If you get it wrong on the first try, can you resize your rings after you buy them? The answer is yes. At Austen & Blake, we provide a complimentary one-time re-sizing service for most rings and wedding bands purchased from our store until 30 days of dispatch. However, we only accept new rings in their original condition.

After the 30-day period, you’ll need to pay additional fees to get your ring resized. Depending on your needs, this can cost upwards of £69, including delivery and insurance costs. However, due to their complexity, we cannot resize bespoke items and full eternity rings.

Design your custom engagement ring at Austen & Blake Today

What if I can’t find the size I’m looking for? If you’ve been trying to find the right fit but are still unsure, the most accurate way to get your perfect engagement ring size is to have your or your partner sized at one of our locations in London, Manchester, Sheffield or many more locations around the country.

A bespoke engagement ring may be the perfect option if you're looking for something truly special. Working with a skilled jeweller, you can design a unique ring that represents your relationship in the best way possible. We can customise every element to suit your style and budget, from the cut of the diamond to the setting and band.
Once you’re ready, you can schedule your appointment online so we can reserve a slot for you. You can also reach out to us at +44 (0)20 7660 1529 or [email protected] if you have any questions about sizing your ring.


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