Ring Size Guide

Last updated on December 27, 2022

Whether you are shopping for an engagement ring, wedding band or an eternity ring, knowing your ring size in advance is important. Although you can always get your ring resized if it does not fit perfectly, having the correct size from the start will save your time and money. This ring size guide includes all the necessary information to help you with the right choice.

What Is Ring Size?

The ring sizes are numbers or letters linked with the inner diameter or circumference of the ring’s band. Although sizes are measured in millimetres or inches depending on the location, different countries have different scales of numbers or letters to define their standard ring sizes.

According to ISO (International Organization for Standardization), to specify ring size during manufacturing steps, jewellers should use a metric ring stick with defined characteristics with an accepted tolerance of ± 0.02 mm between each size. The ISO standard is based on the internal circumference and is called the European system. This system is widely used in Austria, Belgium, Finland, France, the Middle East, Norway, Russia, Sweden and sometimes Germany.

There is also the German system which is based on the internal diameter and is sometimes used in Argentina, Germany and Russia. The third most popular ring size standard is the Swiss system based on the internal circumference minus 40 and is used in Italy, Netherlands, Spain and Switzerland.

In the United States and Canada, ring sizes range from 3 to 13, including quarter and half sizes. In the United Kingdom and Australia, ring sizes range from F to Z, while China and Japan use a numeral sizing system, but their range goes from 4 to 27.

What to Consider When Determining Ring Size

Determining your ring size may seem easy; however, several aspects may affect the measurement. For example, your environment and activity can impact your fingers. Fingers can change size from temperature fluctuations, diet, pregnancy and other personal features.

Also, we should consider that different kind of fingers impact the ring size and its perfect fit. Some people have knotted fingers where the knuckle in the middle of the finger is the widest part. The ring has to fit over the knuckle but sit possibly tight at the base of the finger. In such a case, the best option is to fit the knuckle and add ring-sizing beads to your design. The beads are soldered to the interior of the ring and act as pressure points to keep the ring in place.

Another aspect to consider is the band width. The more metal around your finger, the more space it takes up, meaning it fits tighter. Following this logic, rings with thinner bands tend to have a bit loose fit, so finding the correct size is super important to keep it from spinning.

Last but not least, pay attention to your finger-measuring conditions. For example, warm weather makes our fingers swell, while cold weather makes them shrink. Also, our fingers can swell from any strenuous activity, which is why it is best to get measured when you are relaxed around the middle of the day at room temperature.

Ring Size Conversion Chart

How to Measure Ring Size

There are different at-home methods of measuring your ring size, such as the paper or string technique, using a ring sizer or one of the rings you already own, or if you do not trust your judgement, you can get professionally measured.

For the paper method, you will need to wrap a thin piece of paper around the finger you will wear your ring. Remember to keep the paper close to your knuckle as it is the area where the ring would hit. Make sure the wrap is not too tight or loose, and the paper fits comfortably. Next, you will need a pencil to mark the spot where the ends of the paper overlap. Measure the length of the paper against a ruler and compare the measurement to the circumferences on our chart. For the most accurate results, measure the finger three to four times.

Instead of a thin piece of paper, you can use a string, but it is a less comfortable and reliable alternative as the string is thin and more likely to move around.

The ring sizer technique is another at-home method of measuring your ring size. You can either get a free ring sizer at a jeweller’s or purchase it online. You will need to wrap the sizer around the base of your finger and side the pointed end through the cut until it fits comfortably. The displayed number will be your ring size.

For the ring technique, you will need one of the rings you already own. Make sure the ring you took fits comfortably on your finger and place it against a ruler. You need to measure the inner diameter of the ring and compare the result to the diameters on our chart.

Although at-home methods are handy, especially if you are shopping online, sometimes it is better to turn to a professional jeweller to get accurate measurements. Jewellers use special sizing rings, which are a set of rings in each size you can try on to determine the most comfortable fit. It is worth mentioning that the set of sizing rings may vary by jeweller. Some use a standard set, and others use a specially designed set of rings that reflects their band widths and designs.

How to Get Your Ring Resized

Whether you got the wrong measurements or your finger changed its size with time, you can always have your ring resized by a professional jeweller.

Jewellers can typically alter rings up to two sizes up or down without compromising the band’s integrity. However, depending on the design, the jeweller might need to make a new band for you. This applies to the rings featuring gemstones around the entire band, so be wary with your ring size when purchasing full eternity bands.

The ring resizing process requires adding or removing tiny amounts of precious metal depending on whether you request to make it smaller or larger. The changes are visually imperceptible, but your band may get slightly thinner or thicker after resizing. It is normal to get your ring resized two or three times, but resizing up and down can take a toll as frequent resizing is not good for the metal.

Featured image: CSA-Plastock / Canva