Measure a ring
Align the inside edge of a ring with the screen guide to estimate diameter.
What you can do
Practical tools for the moments you need them.
Measure a finger
Use the on-screen ruler with a strip or string to estimate circumference.
Keep size notes
Save people and ring details, including an optional reference photo selected by you.
Take a paper guide
Export a printable PDF sizer for another way to compare sizes.
How it works
Start in the app and stay in control of the result.
- Calibrate. Use a known card or coin to set the screen scale.
- Measure. Align carefully and read the size conversion.
- Confirm. Check the result with a jeweler or physical sizer before a costly purchase.
Sizing is an estimate: Screen scale, display zoom, ring shape and finger changes affect fit. This is a shopping aid, not a precise instrument or health measurement.
Privacy, explained plainly
Measurements, calibration and saved profiles remain in the app's local storage. Adding a ring photo uses the system picker for the photo you select. Apple handles purchases and any sharing destination you choose.
Read the full Privacy Policy.
Frequently asked questions
- How accurate is a screen reading?
- It is an estimate. Calibrate the screen, align the inner edge carefully, and verify with a physical sizer or jeweler before ordering.
- Does it need camera or photo library permission?
- The core sizing tools do not. An optional ring reference photo is selected using the system photo picker.
- Can it measure my health?
- No. RingMeter estimates jewelry fit; it does not assess health or make a medical measurement.
- What is paid?
- Measurement and saved-profile controls are gated by Pro in the current app. Review the in-app purchase screen for subscription or lifetime terms and local prices.
At a glance
- iPhone and iPad; iOS 17 or later
- No camera needed for sizing; optional system photo picker for ring records
- Confirm size with a physical sizer or jeweler