Calculadora de Tamanho de Calcinha/Sutiã
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
aro = underbust arredondado; copo: diff 1cm=A, 2cm=B, 3cm=C, 4cm=D
About this calculator
This bra size calculator helps you find the band size (underbust circumference) and cup letter (difference between bust and underbust) easily. Simply enter measurements in centimeters: the fullest part of the bust and the underbust. The tool rounds the underbust to the nearest whole number for band size and calculates the difference between bust and underbust to determine cup size, following the table: 1 cm difference = A cup, 2 cm = B, 3 cm = C, 4 cm = D. It's an initial guide, as the perfect fit may vary by brand and style.
When to use? Ideal for buying lingerie online, checking sizes before going to a store, or when unsure between nearby sizes. Also useful for seamstresses needing a reference for custom garments. Measure without clothes or with a light bra, using a tape measure snug but not tight. Accurate measurements are key for a reliable result.
Important care: this calculator does not replace a physical fitting, as each brand has its own size chart. The result is an estimate based on a standard table (1 cm per cup). If your difference is greater than 4 cm, consider larger cups (E, F, etc.) not included here. Also, breast shape and back width affect fit. Always check the tape measure: it should be straight, level, and not twisted.
Frequently asked questions
How to measure bust and underbust correctly?
Use a soft tape measure. For underbust, measure right under the breasts, snug but not tight. For bust, measure at the fullest part, tape straight and loose.
What if the difference is greater than 4 cm?
This calculator covers cups A to D only. For differences above 4 cm, check brand charts that include cups E, F, etc., or try larger sizes.
Is the result the same for all brands?
No. Each brand has its own size chart. Use the result as a starting point and always try on or consult the brand's size guide.
Should I wear a bra when measuring?
Ideally measure without a bra or with a light bra that doesn't change shape. Avoid padded or push-up bras.
How to know if the bra fits correctly?
The band should not ride up at the back, the center should lie flat on your chest, and breasts should not spill out or have gaps in the cup. Straps should not dig into shoulders.