ring size finder and converter
Ring Sizer
A ring size finder and converter before you buy online.
Ring Sizer is a ring size finder app for estimating, converting, and saving ring sizes before checkout, whether you have a ring that fits, need a paper or string guide, or want to compare US, EU, and UK sizes.
Designed for iPhone. The App Store link will be added when the listing is live.
Product view
A practical ring size helper for the moment before checkout.
The app focuses on purchase confidence: estimate a size, compare systems, keep a local note, and remember that brands and ring styles can still vary.
01
Estimate from a ring that already fits
Use the existing-ring flow to enter or measure inner diameter, then review the closest EU, US, UK, diameter, and circumference values.
02
Convert before you order
Compare common ring size systems in one place so a seller listing, regional chart, or millimeter measurement is easier to understand.
03
Save sizes for real buying situations
Keep local entries for yourself, different fingers, or a gift idea, with notes that help when you return to a store page later.
How Ring Sizer fits into online ring shopping
01
Start with the best clue you have
Measure a ring that already fits, use a paper or string guide, or enter a known diameter, circumference, or regional size.
02
Compare the result across systems
Review US, EU, UK, diameter, and circumference values before matching the size to the seller listing.
03
Save the decision with context
Store the estimate locally with a finger, person, gift note, or shopping reminder, then confirm final fit with the seller or a jeweler when needed.
Local size notes, no account required
Ring Sizer stores saved size entries, labels, finger selections, and notes locally on your device and does not require an account. If premium access is used, Apple handles billing and RevenueCat may process technical purchase and entitlement data required to unlock or restore access.
FAQ
Common questions before you install.
What is Ring Sizer for?
Ring Sizer is a ring size finder and converter for estimating, comparing, and saving ring sizes before buying rings online.
Can I measure a ring I already own?
Yes. The app includes an existing-ring flow for estimating size from the inner diameter of a ring that already fits.
Which ring size systems does it support?
Ring Sizer is built around common shopping formats such as US, EU, UK, diameter, and circumference, so you can compare seller charts more easily.
Does Ring Sizer guarantee that a ring will fit?
No. Ring sizes can vary by brand, ring style, band width, and measurement method. The app gives practical estimates and shopping guidance, not a fit guarantee.
Does Ring Sizer need an account?
No. Core use does not require an account, and saved ring size entries are stored locally on your device.
Ready to try Ring Sizer?
The App Store link will be added here when the Ring Sizer listing is live.