Bra Size Calculator

Finding the right bra size can be surprisingly tricky — studies suggest that up to 80% of women wear the wrong size, which can cause discomfort, shoulder grooving, back pain, and poor posture. This calculator takes just two measurements — your band (snug under the bust) and your bust (the fullest part) — and converts them into a band number and cup letter, shown in US, UK, and EU sizing so you can shop across Indian and international brands with confidence.

Who this is for

It helps anyone buying a bra online in India — where you cannot try before you buy — get a reliable starting size for brands like Enamor, Zivame, Clovia, Nykaa, Wacoal, and Triumph. It is equally useful if your weight has changed, after pregnancy or breastfeeding, when a current bra has started to feel tight or loose, or simply if you have never been measured and want a number to begin from before reading a brand's own size chart.

A general guide, not a professional fitting

Two tape measurements cannot capture everything that decides fit — breast shape, tissue softness, how a brand cuts its cups, wire width, and how the band stretches all matter. Treat the result as a screening estimate and a sensible place to start, not a guarantee. Bodies are also rarely symmetrical, so if your two sides differ, fit to the larger one. For the most accurate result, try the calculated size plus its sister sizes (shown with your result) and, where you can, get measured in person by a trained fitter.

How to measure correctly

Band measurement: measure snugly around your ribcage, directly under your bust. The tape should be level all the way round and snug but not tight. Bust measurement: measure around the fullest part of your chest (usually across the nipples) while wearing a non-padded, well-fitting bra. Keep the tape parallel to the floor and breathe normally — don't puff out or hold your breath. Indian DTC brands accept measurements in either inches or centimetres on their size guides, and this calculator lets you switch units and converts for you.

How band and cup size are worked out

The band size comes from your underbust measurement rounded to the nearest even number (bra bands run 32, 34, 36, and so on), since modern sizing measures snugly rather than using the old “add 4–5 inches” rule. The cup size is the difference between your bust and your band: 1" difference = A cup, 2" = B, 3" = C, 4" = D, 5" = DD, 6" = DDD/E, 7" = F, 8" = G, 9" = H. Each extra inch of difference is one cup letter up. Cup volume is relative to the band — a 32D holds the same volume as a 34C, which is why these are called sister sizes.

India and UK sizing

Most Indian lingerie brands follow the UK system, which shares the same band numbers and cup letters this calculator gives for US (US DD ≈ UK DD). EU/European sizing instead states the band in centimetres: this calculator converts it as EU band = round(US band × 2.54 ÷ 5) × 5, so a US/UK 34 band becomes EU 85 and a 36 becomes EU 90. When a brand such as Wacoal or Triumph India lists the band in centimetres, match it to the EU band shown in your result.

Worked example (India context)

Suppose your underbust measures 34" and your bust 38". The band is already even, so it stays 34. The cup difference is 38 − 34 = 4", which maps to a D cup, giving US/UK 34D. Converting the band to EU, round(34 × 2.54 ÷ 5) × 5 = round(17.3) × 5 = 85, so the calculator shows EU 85D — the band number you would match on a Wacoal or Triumph chart that lists sizes in centimetres. If the 34 band feels loose but the cups fit, try the sister size 32DD; if it digs in, try 36C.

Common mistakes to avoid

• Using the old “add 4–5 inches” band rule. It oversizes the band and undersizes the cup; measure snugly and use your actual underbust.
• Measuring the band loosely. A loose tape gives too large a band and a bra that rides up at the back. The band, not the straps, should do about 80% of the support.
• Ignoring the cup when the band changes. Going up one band size means going down one cup letter to keep the same volume (and vice-versa) — that is the sister-size rule.
• Assuming one size fits every brand. Cut varies, so always cross-check against the specific brand's chart and read recent reviews.