US Ring & Dress Size Converter
EverydayConvert US ring sizes to EU, UK, Japan, and India standards. Convert US dress sizes to UK, EU, Australian, Italian, and Japanese equivalents. Free lookup table.
Reviewed by the thecalcu.com team · Last updated August 1, 2026
| US/CA | EU/ISO | UK | Japan | India | Dia. (mm) |
|---|---|---|---|---|---|
| 7 | 54.5 | N | 14 | 14 | 17.3 |
| US/CA | EU/ISO | UK | Japan | India | Dia. (mm) |
|---|---|---|---|---|---|
| 3 | 44 | F | 4 | — | 14.1 |
| 3.5 | 45.5 | G | 6 | — | 14.5 |
| 4 | 47 | H | 7 | — | 14.9 |
| 4.5 | 48 | I | 8 | — | 15.3 |
| 5 | 49 | J | 9 | 9 | 15.7 |
| 5.5 | 50.5 | K | 10 | 10 | 16.1 |
| 6 | 52 | L | 12 | 12 | 16.5 |
| 6.5 | 53.5 | M | 13 | 13 | 16.9 |
| 7 | 54.5 | N | 14 | 14 | 17.3 |
| 7.5 | 56 | O | 15 | 15 | 17.7 |
| 8 | 57 | P | 16 | 16 | 18.1 |
| 8.5 | 58.5 | Q | 17 | 17 | 18.5 |
| 9 | 59.5 | R | 18 | 18 | 18.9 |
| 9.5 | 61 | S | 19 | 19 | 19.4 |
| 10 | 62 | T | 20 | 20 | 19.8 |
| 10.5 | 63.5 | U | 21 | 21 | 20.2 |
| 11 | 65 | V | 22 | 22 | 20.6 |
| 11.5 | 66 | W | 23 | 23 | 21 |
| 12 | 67 | X | 24 | 24 | 21.4 |
| 12.5 | 68.5 | Y | 25 | 25 | 21.8 |
| 13 | 70 | Z | 26 | 26 | 22.2 |
What is a Ring & Dress Size?
The US Ring & Dress Size Converter is a free lookup tool that translates US and Canadian clothing and jewellery sizes into every major international standard, covering six ring size systems and six dress size systems simultaneously. Whether you are shopping from a UK retailer, ordering jewellery from a Japanese brand, or buying a saree blouse from an Indian boutique and need a size reference, this converter gives you an accurate equivalent in seconds.
Ring sizes vary dramatically across countries. The US / Canada system uses an abstract numeric scale, while the EU / ISO system expresses size in millimetres of inner circumference, the UK / Ireland / AU / NZ system uses a letter-plus-half-step scale, Japan and East Asia use yet another numeric scale, and India uses a scale that resembles UK numbering with its own offsets. Switching between these without a reference table is error-prone and can result in an ill-fitting ring, a costly mistake with fine jewellery.
Dress sizes are equally fragmented. A US size 8 means something different to a UK retailer, an Italian fashion house, a Japanese brand, and an Indian apparel manufacturer, all four will label the same garment with a different number. Relying on memory or guesswork when shopping internationally almost guarantees sizing errors.
This converter covers both sizing domains in one place. For ring sizes, it uses the inner diameter in millimetres as the universal intermediate unit, ensuring mathematically precise conversions across all six systems. For dress sizes, it maps equivalent sizes using the industry-standard offset tables used by international fashion buyers. You can also use the Clothing Size Converter for women's tops and bottoms between India, US, UK, and EU, and the Shoe Size Converter to complete your full outfit sizing reference.
Why Use a US Ring & Dress Size Converter?
The primary pain point this tool solves is the confusion that arises when international size labels collide, in a store, on an e-commerce platform, or when receiving a gift. Online jewellery and fashion marketplaces list products with wildly inconsistent size labelling, and many brands list only one standard without a chart.
A few concrete scenarios:
- You find a ring on a UK Etsy seller's page listed as "size L½" and need to know if that fits your US size 7 finger.
- You are ordering a dress from a Japanese brand whose product page lists only Japanese sizes.
- A family member in the US wants to gift you jewellery and asks for your ring size, but you only know your Indian size from your local jeweller.
Without a converter, these require internet searching across multiple pages with inconsistent information. This tool consolidates all six ring systems and six dress systems into a single, instant lookup, saving time and reducing the chance of a wrong purchase. Because sizing errors on jewellery are difficult to correct, resizing has limits, and returns are often not accepted, getting the conversion right the first time has real financial value.
Who Should Use This Converter?
Online shoppers buying from international brands will find this tool most useful on a day-to-day basis. Fast fashion and luxury brands alike list products in their home market's sizing, and without a conversion reference you are guessing.
Jewellery buyers and gift-givers need ring size conversions when purchasing from international jewellers on platforms like Etsy, Zales, or direct designer websites. Even a half-size error can make a ring unwearable.
Fashion students and buyers in India working with international trend reports or sourcing garments from US and European wholesale markets need quick dress size lookups. Pair this with the Clothing Size Converter to cover tops, bottoms, and dresses in one workflow.
Wedding planners and stylists coordinating international bridal parties often deal with bridesmaids and groomsmen in different countries who need size conversions for outfits and jewellery ordered from a single supplier.
Travellers and expats shopping abroad, particularly Indians living or working in the US, UK, or Japan, regularly encounter unfamiliar size labels in physical stores where there is no time to search for conversion charts.
What Insights Does the Ring & Dress Size Converter Give You?
Ring size conversions produce a single numeric or alphabetic equivalent in the target system. The converter handles all six standards:
- US / Canada: the familiar 0–13 numeric scale (with halves)
- EU / ISO: inner circumference in mm, typically 44–70 for adult fingers
- UK / Ireland / AU / NZ: alphabetic scale A–Z with half steps
- Japan / China / Korea: numeric scale 1–27 used across East Asia
- India: numeric scale used by Indian jewellers, related to but offset from the UK scale
- Inner Diameter (mm): the physical measurement of the ring's inner opening, the universal anchor for all conversions
If you know your finger's inner diameter in millimetres (measurable at home with a strip of paper and a ruler), converting to any system is entirely unambiguous.
Dress size conversions map between six regional standards: US/Canada, UK/Ireland, EU, AU/NZ, Italy, and Japan. The output tells you which size to select on a brand's dropdown or size chart in that region. Because dress sizing is not tied to a physical measurement (unlike ring sizes), the converted value is the standard industry-table equivalent, not a guaranteed fit, brand-level variation means you should always confirm with the retailer's own size guide when available.
How to use this Ring & Dress Size calculator
- Select your source unit, open the "From" dropdown and choose the size system you already know. For ring conversions, pick from the Ring Size group (e.g., "US / Canada Ring Size"). For dress conversions, pick from the Dress Size group (e.g., "US / Canada Dress Size").
- Select your target unit, open the "To" dropdown and choose the system you want to convert into. Make sure both From and To units are from the same group (both Ring Size, or both Dress Size).
- Enter your current size, type your size into the input field. For ring sizes this is a number (e.g., 7 or 7.5). For dress sizes this is a whole number (e.g., 8 or 12).
- Read the converted result, the equivalent size in your target system appears immediately below the input. For ring conversions via "Inner Diameter (mm)", the result will be a decimal value in millimetres.
- Swap directions, use the swap ⇅ button between the two dropdowns to reverse the conversion instantly. This is useful when you know the target system's size and want to verify what it maps back to.
- Interpret the result, for ring sizes, if the converted value falls between two sizes in the target system, choose the larger size for a comfortable fit. For dress sizes, use the result as a starting point and consult the brand's size chart to confirm, since cut and fabric affect fit independently of the size label.
Show formula & methodology ↓Show less ↑
Formula & Methodology
### Ring Size Conversions All ring size conversions use inner diameter in millimetres as the universal base unit. Every size in every system maps to a diameter value, and conversion is a two-step lookup: 1. Convert source size → inner diameter (mm) 2. Convert inner diameter (mm) → target size US size to inner diameter formula:Diameter (mm) = 11.63 + (US Size × 0.8128)EU / ISO size to inner diameter: EU size represents inner circumference in mm, so:Diameter (mm) = EU Size ÷ πWorked example, US size 7 to EU:Diameter = 11.63 + (7 × 0.8128) = 11.63 + 5.69 = 17.32 mm EU size = 17.32 × π = 54.4 mm → rounds to EU 54A US size 7 is therefore EU size 54. Worked example, US size 7 to India: The India ring size table maps inner diameter 17.3 mm to Indian size approximately 15. (Exact values follow the published table used by the Bureau of Indian Standards and major Indian jewellers.) --- ### Dress Size Conversions Dress size conversions use a fixed offset table derived from international fashion industry standards. There is no single physical formula because dress sizes are based on a combination of bust, waist, and hip measurements that do not scale uniformly across brands. The standard offset relationships used in this converter are: | US Size | UK / AU | EU | Italy | Japan | |---------|---------|-----|-------|-------| | 0 | 4 | 32 | 36 | 5 | | 2 | 6 | 34 | 38 | 7 | | 4 | 8 | 36 | 40 | 9 | | 6 | 10 | 38 | 42 | 11 | | 8 | 12 | 40 | 44 | 13 | | 10 | 14 | 42 | 46 | 15 | | 12 | 16 | 44 | 48 | 17 | | 14 | 18 | 46 | 50 | 19 | Worked example, US size 10 to UK and Japan: - US 10 → UK 14 (offset +4) - US 10 → Japan 15 (odd-number scale, counting up by 2 from Japan 5 at US 0) These offsets reflect the most commonly published equivalences. Actual garment measurements vary by brand, and Italian sizing in particular may differ by ±1 size depending on the fashion house.
Frequently Asked Questions