INSPIRATION
Size Guide For Tiffany Rings
Size Guide For
Tiffany Rings
Whether you’re treating yourself or buying a gift, getting the ring size right is key to a perfect Tiffany moment. In this guide, we’ll walk you through everything you need to confidently find your Tiffany ring size, including sizing tools, expert tips, and a helpful conversion chart.
Understanding Tiffany’s Sizing System
Tiffany & Co. uses the United States (US) standard ring sizing system, which assigns a number to each ring size based on the inner circumference of the ring in millimetres. This numerical sizing format is used across all Tiffany rings, from simple bands to elaborate engagement styles.
Each whole or half US ring size corresponds to a specific inner circumference (the distance around the inside of the ring). For example:
US Size 5 = 49.3 mm
US Size 6 = 51.9 mm
US Size 7 = 54.4 mm
The sizes increase in increments of approximately 1.3 mm in circumference per half size, making this system highly precise and ideal for fine jewellery.
Tiffany rings are typically available in whole and half sizes, with some designs also offered in quarter sizes for an even more tailored fit. Sizes range from US 3 to 13, although availability may vary depending on the ring style.
How to Measure Your Ring Size for Tiffany Rings
Below are two reliable methods to help you identify your Tiffany ring size with confidence.
Measure a Ring You Already Own
If you have a ring that fits the intended finger well, you can use it to determine your Tiffany size.
What You’ll Need:
Steps:
1. Place the ring flat on a table.
2. Use a ruler to measure the internal diameter (straight across the middle, inside edge to inside edge).
3. Match your measurement to the Tiffany sizing chart to find the corresponding US size.
Inside Diameter (mm)
Approx. US/ Tiffany Size
14.9mm
15.3 mm
15.7 mm
16.1 mm
16.5 mm
16.9 mm
17.3 mm
17.7 mm
18.1 mm
18.5 mm
18.9 mm
19.4 mm
19.8 mm
20.2 mm
20.6 mm
21.0 mm
21.4 mm
21.8 mm
22.2 mm
US 4
US 4.5
US 5
US 5.5
US 6
US 6.5
US 7
US 7.5
US 8
US 8.5
US 9
US 9.5
US 10
US 10.5
US 11
US 11.5
US 12
US 12.5
US 13
Tip: Tiffany supplies a printable ring size guide that includes actual-size ring circles — perfect for placing your existing ring on to find the closest match. Just be sure to print it at 100% scale (do not scale to fit) for accurate results.
Use a Paper Measuring Strip
This is a great method if you don’t already have a ring to measure.
What You’ll Need:
(10 cm x 1 cm)
Steps:
1. Wrap the strip snugly around the base of your finger.
2. Mark where the end overlaps the paper.
3. Unroll the strip and measure the length from the end to the mark — this is your finger’s circumference in millimetres.
Make a note of the measurement and use the conversion chart in the next section to find your Tiffany ring size.
Remember not to pull too tightly - the strip should sit firmly but comfortably against your skin. Your knuckle should also be considered if it's significantly larger than the base of your finger.
Expert Tips for Accuracy
Measure in the evening, when fingers are naturally a bit larger.
Warm hands give the most reliable results.
Take multiple measurements and use the average.
If you're between sizes, it's usually best to size up half a size.
For wide bands, you may want to size up for extra comfort.
Tiffany Ring Size
Conversion Chart
Once you’ve measured your finger or an existing ring, use the chart below to find the corresponding Tiffany (US) ring size. The table includes UK ring sizes (commonly used in the UK and Ireland), inner circumference measurements (in millimetres), and the matching Tiffany US size.
If you measured the internal diameter of a ring, look for the closest circumference using the following formula:
Circumference ≈ Diameter × 3.14
Then, simply match your result to the nearest size listed in the table below.
Tiffany US Size
UK Size
Inside Circumference
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
11.5
12
12.5
13
F
G ½
H ½
I ½
J
K ½
L ½
M ½
N ½
P
Q
R
S
T
U
V
W
W ¾
Y
Z
Z+1
42.9 mm
45.5 mm
46.8 mm
48.0 mm
49.3 mm
50.6 mm
51.9 mm
53.1 mm
54.4 mm
55.7 mm
57.0 mm
58.3 mm
59.5 mm
60.8 mm
62.1 mm
63.4 mm
64.6 mm
65.9 mm
67.2 mm
68.5 mm
69.7 mm
How Sizing Differs for Different Ring Styles
Not all rings feel the same on your finger — even if they're technically the same size. The design, width, and structure of a ring can significantly affect how it fits and feels. Understanding these differences can help you choose the most comfortable and secure size for your chosen Tiffany style.
Narrow Bands vs. Wide Bands
Narrow bands (e.g. dainty stacking rings or slim solitaire settings) tend to feel looser on the finger. You may even find that your regular size slips on and off very easily.
Wide bands (such as statement rings or chunky wedding bands) usually feel tighter. The extra surface area adds friction against the skin, especially when sliding over the knuckle.
If you're choosing a ring with a wide band, consider sizing up by half a size to ensure a comfortable fit — especially for all-day wear.
Rings with Large Centre Stones
Rings with prominent settings - such as engagement rings with solitaire or multi-stone designs — may feel different due to their weight and balance.
These rings often sit higher on the finger and may rotate more easily, especially if the fit is too loose.
A secure, snug fit helps keep the centre stone facing up and prevents twisting. Try the ring on while your hands are warm and slightly swollen, and test how much it shifts when you move your hand.
Eternity Rings and Decorative Bands
Full eternity bands, where diamonds or details wrap around the ring, generally cannot be resized due to their continuous design.
Intricate engraved or patterned bands may also have limitations for resizing or may lose design integrity if adjusted.
It’s important to get the size right the first time with these styles. Use multiple measuring methods if needed and consider getting professionally sized.
Finger Shape and Fit Preferences
Everyone’s fingers are shaped a little differently - some people have larger knuckles with slimmer bases, while others have uniform finger width.
If your knuckle is larger than your finger base, you may need a size that slides over the knuckle but feels slightly loose at the base. In that case, sizing beads or a ring adjuster can help improve the fit.
Common Questions About Tiffany Ring Sizing
Here are some frequently asked questions about Tiffany ring sizing:
Are Tiffany rings true to size?
Generally, Tiffany rings are true to size, but factors such as band width and design can affect the fit. It is always best to measure carefully or consult with a jeweller.
How can I find out my Tiffany ring size?
You can use a ring sizer tool, measure an existing ring, or visit a jeweller for a professional fitting. Refer to Tiffany’s size chart for conversions between international standards.
What sizes do Tiffany rings come in?
Tiffany rings are generally available in US sizes 3 to 13, including half sizes. Some designs - particularly engagement rings and wedding bands - may also be available in quarter sizes for an even more tailored fit.
Find Your Perfect Fit
Choosing a Tiffany ring is a special experience — and ensuring it fits beautifully is just as important as finding the right style. Whether you’re shopping for yourself or selecting a gift, understanding how Tiffany’s sizing works gives you the clarity and confidence to choose well.
Now that you know your size, why not explore our curated collection?
We are one of London’s premier vintage and pre-owned luxury jewellery specialists, based in Mayfair at 74 New Bond Street. Our carefully selected range of pre-owned Tiffany & Co. rings is fully inspected and guaranteed for authenticity. Where possible, we also provide the original Certificate of Origin or International Guarantee from the manufacturer.
Browse our Tiffany ring collection or make an appointment to visit us in Mayfair and find your perfect fit in person.