Measure Your Ring Size · Atelier Trampert

Ring size calculator

Enter your measurement, read off the size

Inner diameter of the ring in mm

Enter your measurement — the size appears right away.

The calculation runs right in your browser — your input is not transmitted and not stored.

The ring test

Measure your ring size
on screen.

What are you calibrating with?

Card€2 coin

First, a quick setup: hold a debit or credit card upright against the screen, flush with the bottom of the frame. Then drag the slider until the frame is exactly as wide as the card.

Adjust frame width

Method 1

Measure an existing ring

You need: a ring that fits well on the desired finger · a ruler

01
Choose the right ring
Take a ring that is worn on the same finger of the same hand — left and right often differ by half a size.
02
Measure the inner diameter
Lay the ring on the ruler and measure from one inner edge to the opposite inner edge, straight across the middle. Read it to a tenth of a millimeter.
03
Enter the value
Enter the value in the calculator above under “Existing ring”. If the ring is not perfectly round, take the shortest inner distance.

Method 2

Measure your finger

You need: a strip of paper or a ribbon · a pen · a ruler

01
Prepare the strip
Cut a strip of paper about 1 cm wide — narrow enough to lie neatly around the finger.
02
Wrap it around the finger
Wrap it around the widest part of the finger and pull it snug so that it lies flat but does not cut in. Mark the overlap with a line.
03
Measure the length
Take the strip off, lay it flat and measure up to the mark. This value is the finger circumference in millimeters.
04
Enter the value
Enter it above under “Finger”. In the European system, the circumference in mm corresponds directly to the ring size.

What matters

Five things that skew the result

The time of day. Fingers are slimmest in the morning and thickest in the evening. It is best to measure in the evening at normal room temperature — then the ring also fits on warm days.
Cold hands. In the cold, the finger shrinks noticeably. Coming in from the cold in winter almost always gives a size that is too small.
The knuckle. If it is clearly larger than the base of the finger, the ring has to fit over the knuckle — measure there and not at the thinnest point.
The ring width. Wide bands from about 6 mm fit more snugly. As a rule, you add half a size to a full size for that — we do this with you in the consultation.
When in doubt, larger. A ring that is too loose can be made tighter. One that is too tight will not go over the knuckle — and the disappointment at the decisive moment is great.

If it is meant to stay secret

Finding out the size without asking

Borrow a ring. The most reliable way: take a ring that is worn on the ring finger and measure it using method 1. An impression in a piece of soap or modeling clay works just as well — we then measure it at our end.
A photo with a scale. Lay a ring flat next to a ruler, photograph it from above and send it to us. We calculate the size from it.
Better a little off than not at all. If you are unsure: we make it in the estimated size and adjust it after the proposal. That takes the pressure off.

Unsure? Send us your measurement via WhatsApp or email — we will check it and get back to you.

Ring size table

Circumference, diameter, size

In the European system, the ring size corresponds to the inner circumference in millimeters. The inner diameter follows from it by calculation.

Ring sizes 44 to 70 with inner circumference and inner diameter in millimeters
Ring size	Inner circumference	Inner diameter
44	44 mm	14.0 mm
45	45 mm	14.3 mm
46	46 mm	14.6 mm
47	47 mm	15.0 mm
48	48 mm	15.3 mm
49	49 mm	15.6 mm
50	50 mm	15.9 mm
51	51 mm	16.2 mm
52	52 mm	16.6 mm
53	53 mm	16.9 mm
54	54 mm	17.2 mm
55	55 mm	17.5 mm
56	56 mm	17.8 mm
57	57 mm	18.1 mm
58	58 mm	18.5 mm
59	59 mm	18.8 mm
60	60 mm	19.1 mm
61	61 mm	19.4 mm
62	62 mm	19.7 mm
63	63 mm	20.1 mm
64	64 mm	20.4 mm
65	65 mm	20.7 mm
66	66 mm	21.0 mm
67	67 mm	21.3 mm
68	68 mm	21.6 mm
69	69 mm	22.0 mm
70	70 mm	22.3 mm

To print

A template for the kitchen table

Print this page at actual size (100%, no fit to page). First check the control line: it must be exactly 10 cm long. Then place an existing ring on the circles — the circle you can just still see inside it is your size.

Control line — must measure exactly 10 cm when printed