Virtual Ring Sizing: How to Make Sure Your Customers Get a Perfect Fit

How often do you get customer requests to resize rings bought online? 

Product returns related to resizing are an issue for digital-first and general jewelry brands as more have begun offering online services, prompting the industry to look for viable solutions to the problem. 

Old-style solutions for online customers – such as measuring the circumference of a finger with tape or sending out free plastic ring sizers – are inconvenient and out of date in the era of disruptive technologies. 

However, advanced cameras on modern smartphones have led to the development of virtual ring size measurement tools boasting high precision which help jewelry businesses selling online to reduce ring resizing requests and product returns. 

In this article, you’ll learn about existing virtual ring sizing techniques, find out what’s wrong with them, and get to know how to measure a ring finger online from a photo to achieve an accuracy with a margin of error below 0.1mm. 

Why sizing is a problem for virtual try-ons

According to a jewelry market insider, businesses selling jewelry online see a 15% rate of ring returns for resizing. Although this issue is usually considered at the business model development stage, it’s still a high margin. Especially given that some rings can’t be resized. 

One in five rings sent for resizing needs to be redesigned. For instance, eternity rings with a continuous band of gemstones. Resizing such rings can damage the gemstones, so the returned ring must either be redesigned or a new ring must be made.

This is a common problem for jewelry brands growing online sales. And brands that offer virtual try-ons are no exception.

A virtual try-on offers a seemingly elegant solution – all that is required from the customer is a picture of their hand taken with a smartphone camera. Then they simply pick a ring from 3D renders of jewelry pieces available online. 

But jewelry try-ons rarely offer ring finger measurement. In the best-case scenario, customers get a ring size conversion chart to compare the circumference of the ring finger to after measuring it with tape and a ruler. Let’s be honest, this method is inconvenient and out of date.

Giving customers a virtual ring size measurement tool integrated into a try-on app creates several benefits for jewelry brands: 

• Firstly, it makes customers confident about their choice of ring, helping to build a stronger connection and loyalty to the brand
• Secondly, it allows brands to collect and store information about each customer using the virtual ring sizing
• And last but not least, a virtual ring sizer plugged into jewelry retailers’ try-on apps can cut ring resizing returns

Available solutions and what’s wrong with them

There are dozens of virtual ring sizers available online that rely on one of the following unsophisticated techniques: 

Fitting a finger between two lines on a smartphone screen. This technique has the app user place a finger on a screen between two lines and adjust them with a special scaler until the edges line up with the finger. The app knows the length of the lines, calculates the number of pixels between them and determines the customer’s ring size. 

The problem with this technique is that it doesn’t take into account that a finger’s width varies from the top to the bottom, depending on where the knuckles are. This is why it’s not clear how to adjust the two parallel lines to get the right fit. This is a potential path to inaccuracies in determining a ring size. 

Placing a ring on a circle. This technique has the user measure the circumference of a finger with tape and then place the “tape ring” on a virtual circle on the phone screen. The app will then determine the ring size and show you the result. 

This method is inconvenient for obvious reasons. How many people do you know that carry tape with them? I know none. So, this reduces opportunities for ring shopping to when a customer is at home or possibly work.

Customers can also use circle apps to determine the size of an actual ring. Although again, it’s another missed opportunity if a customer doesn’t wear any rings on the intended finger.

As you can see, these virtual ring sizing techniques allow you to measure a ring size, but they are far from perfect. They don’t take into account the placement of the knuckles on a finger and leave room for improvement in terms of accuracy. 

A better alternative is to measure ring size from a photo of the ring finger taken by a high-resolution smartphone camera. The finger should be placed next to a standard-sized object in the same photo to show the proportions and determine the size. 

We experimented with a credit card, since most people have at least one in their wallet, and received a promising result — a margin of error that doesn’t exceed 0.1mm. 

How to measure a ring finger online with a credit card

Let’s see how this solution works:

• Grab a standard-sized credit card and put it on a flat surface. Make sure the color of the card contrasts with the surface, otherwise it will be challenging for the algorithm to scan the edges, which will affect the accuracy of calculations. For example, a combination of a white credit card on a white table won’t work. 
• Place your hand below the card on the same surface as shown in the picture below.

• Place your smartphone camera directly above the fingers. Make sure that the camera lens is right above the finger that you want to measure, otherwise, there might be inaccuracies.
• Take a photo of your hand and the accompanying card.
• Tap on the ring finger in the photo — you can scale it to accurately place special markers at the top, the bottom and in the middle of the finger. Making three measurements of the finger ensures the anatomical traits of the finger are taken into account and avoids a situation where a ring size is measured by the widest part of the finger, for example on a knuckle. 

• The high-resolution photo and scaling feature allow the algorithm to analyze more pixels in the image and deliver more accurate proportions on the grounds of the dimensions of the credit card (standard width is usually 85.6mm). It calculates the number of pixels in a millimeter in the photo, takes into account the specified dimensions and detects the ring size with the margin of error that doesn’t exceed 0.1mm. 

Pros and cons of measuring a ring finger from a picture

The method of virtual ring sizing using a picture described above achieves high accuracy, but it has both pros and cons.

Let’s summarize the key benefits of the proposed solution:

• A high-resolution image taken by a smartphone camera can detect an accurate ring size with a margin of error around 0.1mm — in ring size conversion charts for Europe, the diameter changes by 0.2mm from one size to another.
• Measuring a finger with three markers detects the perfect fit, offering customers two ring size options — a tight fit and a loose fit.
• Convenience — there’s no need to look for tape or a ruler. People are more likely to have a credit card to hand.

And here are the cons:

• To get the highest accuracy possible, you need to make sure the camera lens is located right above the ring finger. Adjustments can take several shots.
• You need a good smartphone with a high-resolution camera, which limits the number of potential users of the feature.

Postindustria helps jewelry businesses integrate virtual ring sizing services into their e-commerce proposal. Pick what works best for you — a custom application for virtual ring finger measurement or an integrated feature into your jewelry try-on app. Leave us your contact details in the form below and we’ll get in touch to discuss the details!