The same finger. The same hand.
A ring from a different finger or hand can give you a different fit.
A LITTLE MEASURE. A MUCH BETTER FIT.
Free International
Ring Size Calculator
Created by Aagrah Fine Jewels.
For the ring you love. Or the surprise you’re planning.
Measure, convert and find your closest size—all in one place.
Free, always No signup or photo upload 7 sizing systems
01 / MEASURE AN EXISTING RING
A ring that fits is
a good place to start.
Measure straight across the inside of a ring that fits the intended finger. Leave the metal band out.
inner diameter
to inside edge ↗
mm
Try 17.3 mm. Supported range: 14.1–22.2 mm.
A small detail that mattersUse a round ring. An open or adjustable ring won’t give a reliable diameter until it is fitted correctly.
02 / MEASURE YOUR FINGER
Find the fit
around your finger.
Enter the distance around the finger, in millimetres. A proper ring sizer gives a more reliable fit than string or paper.
1
Measure the finger you’ll wear the ring on, when your hands are at a comfortable temperature.
2
The fit should feel comfortable and still pass over your knuckle. Repeat your measurement.
mm
Supported range: 44.30–69.74 mm.
At-home measurements are estimatesString can stretch and paper can crease. Confirm an important purchase with a jeweller’s ring sizer.
03 / YOUR SCREEN, YOUR RING SIZER
First, give your
screen a sense of scale.
Screens come in different sizes. Match a real object before measuring your ring. Nothing is photographed or uploaded.
Coin sizes vary by year and design. Enter your coin’s verified diameter; don’t guess from its value. If unsure, use a card or ruler.
Place the short edge of a standard bank card between the two marks (53.98 mm).
SHORT EDGE OF YOUR CARD
SmallerMatch the real objectLarger
Fine-tune the match
Screen calibrated
Place your ring flat on the screen. Adjust until the inner edge of the green outline meets the inside of your ring, all the way around.
17.3mm inside
14.1 mm22.2 mm
Fine-tune by 0.05 mm
Keep the same zoom and orientation. Recalibrate when moving to another screen. We’ll ask you to recalibrate if the screen scale changes.
04 / ONE RING. DIFFERENT SIZE NAMES.
A size that travels
with you.
Know your size in another country? Choose its system to find the closest equivalents.
Shopping across borders?Use the millimetre measurement to check the seller’s own chart. Japanese and Chinese retailers may use different conventions; this tool uses GIA’s Asia reference.
05 / FOR THE SURPRISE YOU’RE PLANNING
A little secret.
A thoughtful fit.
Buying a surprise ring? Start with what you know.
Start with a rough circumference
We can estimate from a measurement, but not from appearance, height or clothing size.
We’ll show a ±1.5 mm measurement range, not a recommended purchase size.
Keep the surprise. Skip the guesswork.
- Ask a trusted friend or family member if they already know her size.
- When appropriate, measure a ring she wears on the same finger and hand.
- Ask the jeweller about resizing or exchanging before choosing a fixed-size ring.
- An adjustable ring still has a fit range. Check its minimum and maximum size.
Your measurements stay in this browser.How we calculate your size
GOOD MEASUREMENTS, BETTER DECISIONS
A few details make all the difference.
Take a moment to check these
before you choose a size.
Measure when hands feel normal.
Very cold or hot hands can change your measurement. Repeat it to check.
Leave room for the knuckle.
A comfortable ring should pass the joint without slipping off too easily.
A wide band fits differently.
Confirm wider bands and important purchases with a jeweller’s ring sizer.
A HANDY REFERENCEInternational ring size chart
A HANDY REFERENCE
International ring size chart
Closest chart matches. Physical measurements are more useful than assuming two countries’ numbers are identical. Scroll sideways on smaller screens.
| Diameter | Circumference | India | US | UK / AU | EU | Japan / China* |
|---|
*GIA’s Asia convention. A retailer’s Japan or China chart may differ.
A LITTLE MORE CLARITY
Before you
choose your ring.
How accurate is an online ring size calculator?
The conversion is only as accurate as the measurement and the size chart. On-screen measurement requires calibration; finger measurements also depend on fit and knuckle size. For a final fit, use a jeweller’s ring sizer.
What if I’m between two sizes?
Compare the physical diameter with the seller’s chart and try both sizes if possible. Band width and knuckle fit matter, so automatically rounding up isn’t always the right answer.
Can I use a ₹1, ₹2 or ₹10 coin to calibrate?
Yes, if you know that particular coin’s diameter. Coin dimensions vary by issue and design. Enter a verified diameter or use a standard bank card or ruler instead.
Can you work out her ring size from a photo?
No. Appearance, height, weight or clothing size cannot reliably tell us a ring size. The surprise finder suggests respectful ways to get a measurement instead.
Which sizing charts do you use?
We use GIA’s diameter references for US, UK, Australia and the grouped Asia scale, and the diameter column in Tanishq’s Indian chart for India. The chart’s I½ label is normalised from a typographic “1.5”. Circumference is diameter × π; EU is circumference rounded to the nearest millimetre. Each scale is matched independently to its nearest published diameter (ties favour the smaller reference). Japan and China share GIA’s Asia reference here, not a universal national standard.
Supported diameter: 14.1–22.2 mm. Values outside the supported range are not extrapolated. Rounded chart values can differ between brands. Reference review: 24 September 2026.