About Size Meadow
Size Meadow is a small size-chart site with a ring size converter and a printable ring sizer. Enter a finger measurement and it shows the US and European ring size; print the sizer at true scale to measure at home. The formula is written on the page, so you can check every number yourself.
What it does today
The converter turns a finger circumference, a ring’s inside diameter or a US size into the other values. The printable sizer has eleven circles for US sizes 3 to 13, a box to check your printout against a bank card (85.6 × 53.98 mm) and a ruler from 0 to 100 mm. A short guide explains how to measure at home and what to do when you are between sizes.
The formula and its limits
Inside diameter in millimeters = 11.63 + 0.8128 × US size, and the circumference is the diameter × π. European sizes follow ISO 8653, where the size is the inside circumference in millimeters. We show US and European sizes only: UK letters and Japanese sizes differ from maker to maker, and we could not confirm one table to publish, so we send you to the maker’s own chart.
How we checked it
We opened the page in Chrome and compared the converter with a separate calculation: 150 random circumferences (in millimeters and inches), 100 random diameters and every US size from 3 to 13 in half steps, 273 comparisons in all, with no differences. We also printed the sheet to PDF: it is 190 mm wide, the card box measures 85.6 mm, the eleven circles have the right diameters and the sheet fits on one page in Letter and A4.
What Size Meadow does not do
It does not promise how a particular brand’s ring will fit, it does not sell rings or sizers, and it does not carry affiliate links. Sizes are guides; check the maker’s own chart before you buy.
Who runs it
Size Meadow is written and kept up by the Size Meadow Team. We do not publish personal names, credentials or a postal address here. Write to us through the contact page; the privacy policy, terms of use and disclaimer explain the rest.
Frequently asked questions
Is Size Meadow free?
Yes. There is no account and no limit on prints.
Why are UK and Japanese sizes missing?
Charts for them differ between makers, so we point you to the maker’s own chart instead of guessing.
Does it sell rings?
No. There are no sales or affiliate links.
Try the Size Meadow ring size chart.