Engagement ring size varies vastly between people, so when it comes to choosing an engagement ring, getting the size right is important. A ring that doesn't fit properly can be uncomfortable to wear and may even risk falling off. Different finger shapes, lengths, and knuckle sizes can affect this so rings should be custom sized for every person. 

Knowing the average ring size is useful for several reasons. Firstly, it helps jewellers and manufacturers determine the most common sizes to produce, ensuring a better selection for customers. Secondly, if you are planning a surprise proposal or gift, knowing the average size can increase the chances of getting the right fit.

Average women's ring size

The most common ring size for a woman in the UK is between size L – M with an inside circumference of 50.6mm – 51.9mm. This converts to around a size 6 in the US. 

Average men's ring size

For men, the most common ring size in the UK is between size S – T. This will have an inside circumference of 60mm – 61.3mm and is the same as a US size 9.

International ring size conversions

Ring sizes are referred to differently across the world. Feel free to use our average ring size conversion chart below or see our full International Conversion Chart for more sizes.

Ring circumference (inside) (MM)

Britain & Australia

USA & Canada



5 1/2


L 1/2

5 3/4






9 1/8


S 1/2

9 3/4



9 5/8


How to find my ring size?

The most accurate way to get your ring size measured is by going to a Jewellers to get a specialist's opinion but it can be done at home as well. Your ring size can be calculated by wrapping a flexible tape measure around your finger. This can then be compared with our conversion chart. Another way to measure your ring size is to use our FREE downloadable Ring sizer guide which will give you a good indication of what size ring you need.


allure ring sizer

How do I know if my ring fits?

When fitting your ring, it should slide onto your finger with ease but offer a slight resistance as it passes over the knuckle. This ensures a secure fit, preventing the ring from slipping off unintentionally. You also want to make sure it is appropriately snug to prevent excessive twisting, although some engagement rings with large centre stones and halos may still exhibit some movement even when perfectly sized.


What if I don’t know my partner's ring size?

If you’re looking for a surprise engagement ring or even just a thoughtful present but do not know the ring size of the lucky person, it can be estimated. Someone’s ring size can be worked out by visiting a jeweller for a specialist opinion. They will be able to measure another one of their rings and match it for a perfect fit on the engagement ring. If you don’t have access to another ring then it can sometimes be judged based on their height, clothes size, and a picture of their hand. 

Under the circumstance that a ring size cannot accurately be guessed then you should consider a style of engagement ring that can be adjusted. Buying a ring that is bigger than the finger is recommended which means that it can be easily changed afterwards to the correct finger size. A ring that is smaller than the size of the finger can be enlarged however, this is less desirable with an element of risk as it may become thinner and weaker.


Should I just buy the average-size ring?

Buying the average size ring and hoping that it fits can work but it is not the best method as ideally re-sizing should be limited to 2-3 sizes either way. If the size is largely more big or small this can make it difficult for re-sizing it to the correct measurements later on. Although the average ring size for a woman is a size L, this could still be vastly off for an ‘average-sized’ woman. Lots of different factors affect ring sizes including temperature, finger shape, finger length, and knuckle size. This means that a ring should be custom fit for each person to ensure maximum comfort.


Can an engagement ring be re-sized? 

As mentioned above, all rings can be re-sized, not just when originally purchased but also over time. 

Finger size can change based for many reasons. Temperature, lifestyle, and age are just some of the factors that can influence this. However, the majority of rings can be re-sized to fix these problems. Rings can be upsized and downsized depending on the person’s needs.

Whether you have got the average size ring when buying it as a surprise and it doesn't fit or if lifestyle changes have created a need for it to be re-sized then it is better to have a thicker band. A ring will get thinner during the re-sizing process so a thin band will have less material to work with but also has the possibility of becoming brittle. 

In situations when the ring is not able to be re-sized then it can be re-modelled. This means that the components like the gemstones and settings can be removed from the ring and placed onto a new band that will fit you perfectly. Another option for when a ring cannot be re-sized is to add ‘speed bumps’ to the inside of the ring. These are small additions that will decrease the gap between the finger and the ring making a comfortable fit while still keeping your original ring.

Get in contact to enquire about getting your ring re-sized. 


Will re-sizing my engagement ring weaken it?

Re-sizing a ring will only change the size and fit of the ring and not affect the other components. The band of the ring will change to the new size and can become thinner, however, a specialist jeweller will recommend when this is too much of a risk to the ring. When the band is too thin or has gemstones within it then it might be recommended to re-model the ring instead. This saves the old gemstones and settings and places them onto a new band which can be updated and changed to your style or made to match the original.


allure jewellers engagement ring re-size

Choosing the right engagement ring size is a crucial step in creating a memorable and meaningful proposal. By taking the time to determine the correct engagement ring size, you'll be one step closer to creating a moment that will be cherished forever. Discover all our Jewellery Guides to find out more information to help you make the right purchase.