An on-screen ring size gauge and converter for US, UK, EU and Japanese sizes. No camera, no account.
How accurate is the on-screen gauge?
As accurate as your calibration. Screens differ, so the app asks you to hold a bank card against the screen and match its outline once. Every bank card is the same width worldwide (85.6 mm), so this fixes the scale for your particular phone.
Which part of the ring do I match to the circle?
The inside. Lay a ring you already own and that fits well flat on the screen and slide the circle until it sits just inside the band. The reading is the ring’s inside diameter, which is what every size system is based on.
Can I use the size for a ring I am buying online?
Yes. Sizes are shown in US/Canada, UK/Australia, EU (ISO circumference in millimetres) and Japan. Sellers sometimes round differently, so if you fall between two sizes, choose the larger for a wide band and the smaller for a thin one.
Why does a wide band need a bigger size?
A wide band covers more of the finger and fits tighter than a thin one at the same size. The Sizes tab suggests an allowance for bands from 6 mm and up.
Does it use the camera or store my measurements online?
No camera is used. Saved sizes stay on your phone.
Email quicksupport36@gmail.com and describe what happened. Including your device model and iOS version helps.
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