Enter a ring inner diameter or finger circumference in millimetres and instantly find the closest Indian ring size, chart dimensions, international equivalents and a downloadable PDF result.
The Ring Size mm to India Size Converter Tool is built for the most common situation in online jewellery shopping: you know a measurement in millimetres but the seller asks for an Indian ring size. Instead of manually comparing several columns in a chart, enter the mm value, tell the tool whether it is finger circumference or ring inner diameter, and the converter finds the nearest Indian size from the reference table used on this page.
Millimetres are especially useful because ring sizing changes in very small increments. A difference of less than one millimetre can move the closest match to another size. The converter therefore keeps the original mm measurement visible in the result, calculates both diameter and circumference, and shows nearby sizes so you can make a better decision when your reading lands between two chart entries.
For a full reference, open our Ring Size Chart India. If you need US, UK or EU conversion as your starting point, use the India Ring Size Converter. For a guided finger measurement workflow, try the Finger Size Measurement Tool India.
Select whether your mm value is finger circumference or the inside diameter of a ring.
This is the total distance around the finger where the ring will sit. Wrap a non-stretch paper strip around the finger, mark the overlap, lay it flat and measure the length in millimetres. Typical adult measurements commonly fall somewhere in the high 40s to low 60s mm, but there is no universal โnormalโ size.
This is the straight distance across the empty opening inside a ring that already fits. Measure from inner edge to opposite inner edge through the centre. Do not include the thickness of the metal. A caliper is ideal, but a millimetre ruler can work if the ring is placed flat and read carefully.
Use circumference when measuring the finger directly. Use inner diameter when you already own a ring that fits the exact finger and hand.
Ring sizing changes in small increments. Read the ruler or caliper in millimetres and keep at least one decimal place where your measuring tool allows it.
For circumference, measure where the ring will sit and confirm the loop can pass the knuckle. For diameter, measure the empty inside opening of the ring through its centre.
Take three readings. If they are close, use the average. Large differences usually mean the paper moved, the ring was not centred, or the ruler angle changed.
Enter the number in the tool, select circumference or diameter, choose your band preference and calculate the closest Indian ring size.
Compare the result with the jewellerโs own chart or physical ring gauge, especially for engagement rings, custom jewellery, wide bands, eternity rings or designs that are difficult to resize.
For a 17.1 mm inner diameter, 17.1 ร ฯ is about 53.7 mm; the practical chart value used here is listed as 54.0 mm for Indian size 14.
For a 57.0 mm circumference, dividing by ฯ gives about 18.1 mm, close to the 18.0 mm chart diameter shown for Indian size 17.
Published ring-size charts are practical references and often include rounded diameter or circumference values. The converter therefore matches your entered mm value to the chart entries rather than pretending every retail system is an exact mathematical standard. Use the result as a strong starting point, then verify against the sellerโs own sizing system.
Use the circumference column when you measured around the finger. Use the diameter column when you measured the inside opening of an existing ring. The international columns are cross-checks only; a retailer may round conversions differently.
| Indian Size | Diameter (mm) | Circumference (mm) | US | UK | EU |
|---|---|---|---|---|---|
| Indian Size 1 | 13.1 mm | 41.0 mm | 1.75 | B | 41 |
| Indian Size 2 | 13.3 mm | 41.7 mm | 2 | C | 42 |
| Indian Size 3 | 13.7 mm | 42.9 mm | 2.5 | D | 43 |
| Indian Size 4 | 13.9 mm | 43.6 mm | 3 | E | 44 |
| Indian Size 5 | 14.1 mm | 44.2 mm | 3.5 | Fยฝ | 44 |
| Indian Size 6 | 14.5 mm | 45.5 mm | 3.75 | G | 46 |
| Indian Size 7 | 14.9 mm | 47.1 mm | 4.25 | Iยฝ | 47 |
| Indian Size 8 | 15.0 mm | 48.0 mm | 4.5 | J | 48 |
| Indian Size 9 | 15.4 mm | 49.0 mm | 5 | Kยฝ | 49 |
| Indian Size 10 | 15.7 mm | 50.0 mm | 5.5 | Lยฝ | 50 |
| Indian Size 11 | 16.0 mm | 51.2 mm | 5.75 | Mยฝ | 51 |
| Indian Size 12 | 16.4 mm | 51.8 mm | 6 | N | 52 |
| Indian Size 13 | 16.7 mm | 53.1 mm | 6.5 | O | 53 |
| Indian Size 14 | 17.1 mm | 54.0 mm | 7 | P | 54 |
| Indian Size 15 | 17.4 mm | 55.0 mm | 7.25 | Q | 55 |
| Indian Size 16 | 17.8 mm | 56.3 mm | 7.75 | R | 56 |
| Indian Size 17 | 18.0 mm | 57.0 mm | 8 | S | 57 |
| Indian Size 18 | 18.4 mm | 57.8 mm | 8.5 | T | 58 |
| Indian Size 19 | 18.7 mm | 59.1 mm | 9 | U | 59 |
| Indian Size 20 | 19.1 mm | 60.0 mm | 9.5 | V | 60 |
| Indian Size 21 | 19.4 mm | 60.9 mm | 10 | W | 61 |
| Indian Size 22 | 19.7 mm | 61.9 mm | 10.5 | X | 62 |
| Indian Size 23 | 20.0 mm | 62.8 mm | 11 | Y | 63 |
| Indian Size 24 | 20.4 mm | 63.8 mm | 11.5 | Z | 64 |
| Indian Size 25 | 20.7 mm | 64.7 mm | 12 | Z+1 | 65 |
| Indian Size 26 | 21.0 mm | 66.0 mm | 12.5 | Z+2 | 66 |
For a narrow ring, the nearest chart size is often a reasonable starting point. If your measurement is only slightly above a chart value, many people still prefer the nearest size rather than automatically moving up. Comfort, knuckle width and how snugly you like jewellery to sit all matter.
Wide bands contact more skin and usually feel tighter than thin bands at the same nominal size. If your mm measurement is between two sizes, the larger option can be more comfortable. Very wide wedding bands should ideally be checked using a gauge with similar width.
A size that fits the finger base may not pass the knuckle comfortably. Measure both the base and the widest knuckle point. The final choice may need to balance secure wear at the base with enough clearance to remove the ring.
Eternity rings, tension settings and some complex gemstone designs can be difficult or impossible to resize. For these designs, treat an online converter as a pre-check only and confirm the final size professionally before purchase.
Outside diameter includes the ring metal and can make the ring look much larger than its wearable opening. The converter needs the inside diameter.
A value such as 54 mm makes sense as finger circumference, but 54 mm would be an impossible ring inner diameter for ordinary jewellery. Always select the measurement type that matches what you actually measured.
Finger sizes can differ between hands and even between neighbouring fingers. A ring that fits the right ring finger may not fit the left ring finger exactly.
Compressing the skin produces a smaller circumference and can lead to a tight result. The strip should be snug, not constricting.
Temperature, exercise, salt intake and time of day can change finger size. Take several readings under normal conditions instead of trusting one unusual measurement.
Indian and international conversion charts can vary slightly because of rounding or brand-specific systems. Save the mm value with your result so you can compare it directly with the sellerโs own chart.
When shopping online, keep more than the Indian size alone. Save your original mm measurement, the matched Indian size, the reference diameter and circumference, andโif usefulโthe US, UK or EU cross-check. Those values make it easier to compare product listings that use different sizing systems.
For gold jewellery in India, sizing and hallmarking are separate issues. Ring size describes fit; hallmarking concerns precious-metal purity and identification. For official consumer information about hallmarking, see the Bureau of Indian Standards hallmarking overview.
If you are ordering an expensive engagement ring, custom wedding band or a design with stones around the full shank, confirm the final ring size with the seller before production. The cost of a professional sizing check is usually small compared with the inconvenience of remaking or altering a difficult ring.