Rock My Wedding’s promise is to be here from ‘I will’ to ‘I do’, so we had to share this engagement ring size guide to be right there with you from the beginning. Selecting the perfect engagement ring is a momentous decision, and ensuring it fits just right is key. Discovering the ideal ring size can be an exciting yet tricky endeavour. In this comprehensive guide, we unveil expert tips, foolproof methods, and insider secrets on how to accurately find the engagement ring size, guaranteeing a flawless fit for that unforgettable proposal. Dive into our 8 step-by-step tips to help find your partner’s engagement ring size without them knowing! 

How to find your partner’s engagement ring size without them knowing! We’ve got all the tips and tricks you need!

Measuring Your Own Ring Size

What should you consider when measuring your ring size?

Firstly, if you already own a ring that fits on your ring finger, then you can use this to find your engagement ring size. The size of the ring might be engraved on the inside. If it isn’t, you can measure the inner diameter of this ring. One way to do this would be to place your ring on top of a ruler or tape measure. After, check this out on a sizing chart to work out what ring size you have! There are also downloadable apps you can use! Place your ring on your phone or tablet screen and the app will tell you the correct size. 

Fenton also has a ring sizer they can send you free of charge if you don’t have another ring to use as a reference. 

When is the best time to measure your ring size? 

Fenton has a few top tips for ensuring you get an accurate ring fit. Ideally, Fenton suggests taking your ring measurement around mid-afternoon. This will account for the fact your fingers will be smaller in the morning, and ensure the size of your ring will be something which will be comfortable for you all day long. But do take a few measurements at different times of the day, to account for any changes due to temperature. 


Finding Out Your Partner’s Engagement Ring Size

How can you determine your partner's ring size without asking them?

Maxwell Stone, an engagement ring and diamond expert from UK retailer, Steven Stone, says that, “When you’re planning to propose to your partner, you typically want to try and keep it a secret. You also want to make sure that the proposal is perfect and knowing the size of the engagement ring you need is part of creating a special piece of jewellery.


While you can get engagement rings resized after purchase, knowing a general ring size can help the entire proposal go that little bit smoother – and there are a few good tactics to help you find your partner’s ring size.” 


Don’t forget, if you’re ordering your ring from somewhere international or somewhere internationally owned, the ring sizing will be different. Use a standard ring size chart to help you find a similar or the same-sized ring in the correct conversion. 

1. Look through their jewellery box

If you know your partner wears other rings, then having a cheeky look in their jewellery box is a great way to find their engagement ring size. For the closest fit, look for rings worn on the ring finger on the right hand, or the middle finger of the left hand. Then, simply use a ring sizer tool, app or ruler to measure the diameter of the ring.

2. Take one of their rings to a jeweller

Is your partner super observant? Do they wear their rings every day? If yes, you might find this one a bit harder. But,  taking one of their favourite rings to a jeweller for sizing is an accurate way to go. This process can take seconds! The challenge is finding a ring they wear often and find comfortable but won’t notice is missing. If you have to secretly take a ring that your partner wears on their dominant hand, remember that dominant hands tend to be slightly larger. If they are right-handed you will need to size down, and if they are left-handed you may need to size up.

3. Create a ring sketch

For this method, you should draw along the inside of the ring and the outside, so your jeweller knows the diameter and circumference. All you need to do then is take this sketch to your jeweller. Try and choose a ring that is a similar width to your partner’s preferred engagement ring. Wider rings fit tighter on the finger than slimmer engagement ring bands, so keep this in mind when creating your sketch.

4. Use a piece of string

Okay, this one requires a lot of stealth. If your partner is a light sleeper, it’s best to try one of the other methods we’ve suggested. When your partner is asleep and deep in the dream world, wrap a small piece of string around their ring finger and use a pen to mark where the ends meet. The string will then tell your jeweller the size you need. 

5. Ask friends or family

If a friend has an engagement ring, encourage them to let your partner try the ring on. The friend can then let you know if the ring is too big, too small or just right for your beloved. Perhaps your partner’s family has an heirloom or vintage piece they can try on for size in a subtle way. Also, a mother knows best. Your beau’s parents might know their ring size already if they’ve bought them jewellery as a gift before! Getting your partner’s family involved has the added benefit of making everyone even more excited about your proposal! 

6. Take them shopping

If you have a friend or family member with a birthday coming up, you could take your partner shopping for the perfect gift with you. Get your partner to model the ‘options’, so you can work out their size. Plus, since you’re already at the jeweller, you can always ask your partner to point out diamond rings, gemstone rings and precious metal colours that they like. This will help you discover the diamond engagement ring style and engagement ring design features they like the most too. However, this might be a bit too on the nose for some. If you know your partner would prefer a complete surprise, this isn’t the right choice for you. 

7. Compare your own or a sibling’s fingers

No idea how to find your partner’s engagement ring size? The best thing to do if you have no idea is to try on the ring yourself or, at least, get a sibling or friend who might have similar-sized hands. This method is far from perfect for finding the correct engagement ring size, but it will be better than guessing. Try to size up rather than going too small. It is typically easier for jewellers to resize an engagement ring when it’s a bit too large.

8. Choose a proposal ring instead

What is a proposal ring? We hear you ask and we’re here to answer. A proposal ring is different from an engagement ring because a proposal ring is bought just for that. The proposal. It’s normally a cheaper transition ring that you use to propose with but it is one that will eventually be replaced with that dream engagement ring. You might choose this option if you know your partner has very specific tastes and you want to shop for one together at a later date. You might also choose for financial reasons or just because you don’t care for tradition. 

Can you get your engagement ring resized? Yes! It's the thought that counts. It isn’t the end of the world if the ring doesn’t fit

Now you know how to find your engagement ring size! The next step is the actual proposal. How are you going to do it? Luckily for you, if you’re struggling with putting your feelings into words, you can use our proposal speech ideas with examples and templates to help you put together a speech anyone would be saying ‘YES!’ to. Whoever you’re proposing to will most likely want to take that iconic engagement ring selfie. Our tip to you is to make sure your beau has their engagement nails done! 

Leah Blundell

Written by Leah Blundell

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