About Us

RingFit helps you estimate a ring size using a screen or a measurement you already have.

What we do

Use a ring that fits, calibrate the screen against a standard bank card and match its inside opening. If you do not have a ring, measure your finger with paper or a flexible tape and enter its circumference. Manual measurements work in millimeters, centimeters and inches.

How the estimate works

US and Canada estimates use the Tiffany & Co. published size chart, covering US 3 to 13 in half sizes. We choose the closest chart measurement. Approximate EU sizes use rounded circumference in millimeters. Diameter and circumference conversions use the mathematical relationship C = π × d.

Indian estimates use the nearest diameter or circumference in BlueStone’s published size 6–30 chart. This is a retailer reference, not a universal guarantee of fit. Measurements below or above that chart are not assigned an Indian size. You can calibrate using a standard bank card or a 3 cm length on a ruler.

Our approach

We require calibration before displaying an on-screen measurement result, make the source of the size chart clear, and explain the limits of an estimate. The tool runs in your browser; it does not need a photograph of your hand or bank card.

What RingFit cannot tell you

A screen cannot automatically detect a ring or guarantee how a particular style will fit. Band width, ring shape and retailer sizing can differ. For important purchases, confirm the fit with a jeweller or a physical sizing kit. Use a manufacturer’s own kit for smart rings.

Independent tool

RingFit is an independent measurement website, not a jewellery retailer or professional fitting service. Referencing a size chart does not imply affiliation or endorsement. The current site is a private preview shared by its owner.

International comparisons

US / Canada and UK references use Tiffany & Co.; Australian references use Diamond Gallery; Indian references use BlueStone; Japanese references use L&Co. EU estimates round circumference in millimeters. The calculator names these references because retailer charts can differ. The converter finds the nearest available entry using circumference and marks measurements beyond a chart’s bounds.

Contact us

Questions or feedback about RingFit? Email [email protected].