DIAMETRO vs Ringa

Find your ring size in seconds, right on your iPhone. Place a ring you already own on the calibrated circle, slide until the bubble fills the inside of the ring, and DIAMETRO shows its size in EU/ISO, US, UK, CH and JP, plus the exact diameter and circumference. HOW IT WORKS • Calibrate once with a bank card or a coin for true physical scale • Lay your ring on the screen • Slide until it fits, then save the result DIAMETRO PRO • Finger measurement: enter the circumference of your finger and get a recommended size, with optional knuckle compensation • All accent colors • Unlimited saved measurements • Printable PDF sizer, export and backup (PDF, CSV, JSON) ALSO INSIDE • Light and Dark mode • English, Romanian and French PRIVATE BY DESIGN No account. No tracking. Your measurements stay on your device. Conversions are approximate. Confirm your size with a jeweler before buying.

Find your ring size on your phone, with a ring you already own or with your finger, and any bank card. No sign-up: ring sizing and the full result are always free. HOW IT WORKS 1. Calibrate once. Lay a bank card on the screen and match one line to its edge. Ringa learns the true size of your screen. 2. Measure. Place a ring that fits you on the screen and fit the circle to its inner edge. Smaller and Larger buttons fine-tune it by a tenth of a millimeter. 3. Read your size. The inner diameter in mm and your size in every common system, side by side. Not sure what to do? Each step has a short animation that plays the first time, and How? shows it again. NO RING AT HAND Switch to With your finger. Lay the finger flat on the screen and mark the width at its root and at the knuckle. Ringa estimates your ring size to within one size and says so on the result. When you can, check it with a ring. ONE MEASUREMENT, EVERY SIZE SYSTEM US and Canada, UK and Australia (letters), Europe (circumference), Japan, Switzerland, India, Türkiye and inner diameter in mm. Handy when you shop from a jeweler abroad. HONEST BY DESIGN A phone screen is not a jeweler's mandrel. Ringa always shows the millimeters, says a ring measurement is accurate to about half a size, and suggests the larger size when you land between two. Tips cover the rest: measure in the evening, warm hands first, wide bands need half a size up. SIZES FOR THE PEOPLE YOU LOVE Save a result to yourself or to someone else and find it again in Settings under People. Planning a proposal or a gift? Borrow one of their rings for a minute, measure it and keep the size for the day you shop. Share the result with the jeweler in one tap. PRIVATE No account. Your calibration, people and sizes stay on your phone. 16 languages. JEWELRY PACK One optional purchase opens more true-size tools: bangle size; a solitaire diamond at true size on your own ring size, from 0.25 to 2 carats; for watches, band (lug) width, wrist and bracelet size with a paper strip, and your watch at true size on your wrist; and My stone, your birthstone and zodiac stone at true size on your finger. Ringa is free and supported by ads. At most one full-screen ad may appear after you confirm a measurement, before the result. There are no ads while you calibrate or measure, and the result is never locked. Optional: the Jewelry Pack, a one-time in-app purchase, with bangle sizes and no full-screen ads. You can restore the pack on your other devices with the same Apple ID.