RingSizer vs Ring Sizer

RingSizer turns your iPhone into a precision jeweler's tool — no ring sizer, no guesswork, no trip to the store. MEASURE YOUR RING Already have a ring that fits? Place it flat on your screen and align it with the on-screen guide. RingSizer uses your device's exact screen dimensions — with optional bank-card calibration for extra precision — to calculate your true size. MEASURE YOUR FINGER No ring on hand? Use the two-step Ellipse Method. Fingers aren't perfectly round, so RingSizer measures both width and thickness for a scientifically accurate fit, based on the same math jewelers use. CONVERT BETWEEN SYSTEMS Instantly convert between EU, US, UK, Japanese, Australian and Swiss/German ring sizes — or look up any size by diameter and circumference. LIFE-SIZE RULER A true-to-scale on-screen ruler for measuring anything small, in mm, cm or inches. FEATURES • High-accuracy ellipse-based finger measurement • Bank-card screen calibration for pixel-perfect results • Worldwide size conversion (EU, US, UK, JP, AU, CH/DE) • Save and organize your measurement history • Evening measurement reminder — fingers swell throughout the day, so a second reading helps you land on your truest size • Private by design — your measurements never leave your device RingSizer Premium unlocks unlimited history, expert fitting advice, and full worldwide size conversion — with a one-time purchase, no subscription. Whether you're buying a ring as a surprise, replacing a lost one, or shopping online, RingSizer gives you a confident, accurate answer in seconds.

Estimate your ring size with your iPhone camera and a standard-sized card. Measure an existing ring or a finger, check the detected edges, and compare sizes across international charts. MEASURE WITH A PHOTO Place a ring on or beside an 85.60 × 53.98 mm card on a flat surface. For fingers, place the card above a relaxed, spread-out hand. Use the level guide, take a photo, or choose an existing picture. The app uses the card as a scale reference and corrects perspective in the card’s plane. CHECK THE FIT Review the card corners and ring’s inner edge with a magnifying view. Move the ring circle’s center or radius to refine the result. For fingers, slide the measurement along the detected finger to check a wider section or knuckle. CONVERT RING SIZES Compare 15 sizing systems, including US/Canada, UK/Australia, European circumference, Japan, Hong Kong, mainland China, Taiwan, India, Brazil, South Korea, Argentina and Chile. Choose your country, preferred size system, and millimeters or inches. Published charts vary, so check your jeweler’s chart before ordering. KEEP YOUR MEASUREMENTS Save results, photos and adjustments in History. Reopen a measurement to review it, add a note, or compare sizes. Your measurement folders are also available in the Files app. Delete one measurement or clear them all in Settings. ON-DEVICE PROCESSING Measurement photos are processed on your iPhone. No account, advertising or tracking is required. The app does not upload measurement photos to a server. iOS backups and files you choose to share are controlled by you. BEFORE YOU ORDER Results are estimates, not a guaranteed fit. Lighting, camera angle, object height and card placement can affect accuracy. Finger circumference is estimated from visible width; fingers are not perfect circles. Scan a few times and confirm with a physical ring sizer or jeweler before purchasing. Terms of Use: https://www.x-tech.io/apps/ringsizer/terms Privacy Policy: https://www.x-tech.io/apps/ringsizer/privacy