Bra Size Calculator UK
Use our free UK bra size calculator to determine your perfect fit. This bra calculator UK tool helps you learn how to measure bra size correctly, check your bra size, and find the right bra size using UK sizing standards. Whether you're wondering "what bra size am I?" or need to figure out your bra size, our calculator provides accurate measurements instantly.
Measure around your ribcage, just under your bust
Measure around the fullest part of your bust
How to Measure Your Bra Size (UK) - Complete Guide
Learning how to measure your bra size is the first step to finding the perfect fit. This UK bra calculator helps you determine your bra size accurately. If you're asking yourself "what is my bra size?" or "how do I find my bra size?", our step-by-step guide will show you exactly how to measure bra size using UK standards.
Our bra calculator UK uses the same method as professional fitters. To check your bra size or work out your bra size, you'll need to take two simple measurements. This bra size calculator UK tool then calculates your band size and cup size automatically, making it easy to figure out your bra size without confusion.
Tip: For the most accurate measurement, wear a non-padded bra or no bra, and have someone help you measure if possible. Measurements should be taken while standing straight with arms at your sides. This ensures you get the most precise results from our bra calculator.
How to Measure Bra Size Calculator - Step-by-Step Guide
Our bra calculator makes it simple to determine your bra size. Follow these steps to measure your bra size correctly and get accurate results from our UK bra calculator. This method works whether you're learning how to measure bra cup size or need to check your overall bra size.
- How to measure your under bust: Wrap a measuring tape around your ribcage, directly under your bust. Make sure the tape is level and snug but not tight. This measurement determines your band size. Round to the nearest even number (e.g., 31" rounds to 32", 33" rounds to 34"). This is the first measurement our bra calculator needs.
- How to measure bra cup size: Wrap the measuring tape around the fullest part of your bust, typically at nipple level. Keep the tape level and parallel to the ground. Don't pull too tight - the tape should be snug but not compressing your breasts. This measurement helps determine your cup size.
- Calculate the difference: Our bra calculator automatically subtracts your band size from your bust measurement. The difference determines your cup size according to UK sizing standards. This is how you work out bra size accurately.
- Find your size: Enter your measurements into our bra size calculator UK above, and it will instantly tell you what bra size you are. The calculator shows both your band size and cup size, giving you your complete UK bra size.
This bra calculator UK method is the same one used by professional fitters. Whether you need to figure out your bra size for the first time or check if your current size is correct, our calculator provides reliable results. Many people discover they've been wearing the wrong size, so using a bra calculator to determine your bra size is essential for comfort and support.
UK Cup Size Chart
The cup size is determined by the difference between your bust measurement and band size:
UK Bra Calculator vs Other Sizing Systems
Our UK bra calculator uses UK sizing standards, which differ from other systems. Understanding these differences helps you find the right bra size when shopping from different brands or regions. This UK bra calculator is specifically designed for UK sizing, so if you're in the UK or shopping from UK brands, this is the right calculator for you.
UK Bra Calculator Sizing
UK bra sizes use double letters (DD, FF, GG, HH, JJ, KK) which are unique to the UK system. This bra calculator UK uses UK sizing standards, making it perfect for UK shoppers. Many popular UK brands use this same sizing system, so our calculator will help you find the right size for UK brands.
US Sizing
US sizing is similar but uses DDD instead of E, and doesn't use all the double letters. A UK E cup is equivalent to a US DDD cup. US brands use different sizing standards, so if you're shopping from US brands, you'll need to convert the size.
EU Sizing
European sizing uses different band sizes (often in centimeters) and a different cup progression. UK band sizes are typically 4 inches larger than EU band sizes. Our UK bra calculator won't work for EU sizing - you'd need a different calculator.
How to Find the Right Bra Size - Sister Size Calculator
Sometimes the bra size our calculator gives you might not fit perfectly in every brand or style. This is where understanding sister sizes becomes important. A sister size bra calculator helps you find alternative sizes with the same cup volume but different band sizes.
For example, if our bra calculator gives you 34C but the band feels too tight, you can try 36B (one band size up, one cup size down) or 32D (one band size down, one cup size up). These are sister sizes - they have the same cup volume but different band sizes. Our bra calculator shows your primary size, but knowing your sister sizes helps you find the right bra size across different brands.
Sister Size Rule: When you go up one band size, go down one cup size. When you go down one band size, go up one cup size. This maintains the same cup volume. For example: 32D = 34C = 36B (all have the same cup volume).
How to Fit a Bra - Getting the Perfect Fit
Once you've used our bra calculator to determine your bra size, the next step is learning how to fit a bra properly. Even if our calculator gives you the correct size, knowing how to fit a bra ensures maximum comfort and support. Here's how to check if your bra fits correctly after using our bra size calculator.
After using our bra calculator UK to find your size, try on bras in that size. The band should be snug but comfortable on the loosest hook (you'll use tighter hooks as the bra stretches over time). The cups should fully contain your breasts without gaping or spilling. The center gore (the piece between the cups) should lie flat against your chest. If any of these don't fit correctly, you may need to try a sister size or adjust based on the specific bra style.
Tips for the Perfect Fit
Frequently Asked Questions
Why is my calculated size different from what I usually wear?
Bra sizing can vary between brands and styles. The calculated size is a starting point. You may need to try a sister size (same cup volume, different band) or adjust based on the specific bra style. For example, if 34C feels tight in the band, try 36B (sister size).
What is a sister size?
Sister sizes have the same cup volume but different band sizes. For example, 32D, 34C, and 36B all have the same cup volume. If your band size is between sizes or a brand runs small/large, you can try a sister size.
How often should I remeasure my bra size?
It's recommended to remeasure every 6-12 months, or after significant weight changes, pregnancy, or breastfeeding. Your bra size can change due to weight fluctuations, hormonal changes, or age.
Should I measure with or without a bra?
For the most accurate measurement, measure without a bra or in a non-padded bra. If you're wearing a bra, make sure it's not compressing or altering your natural shape.
What if my measurements fall between sizes?
If your under bust measurement is odd (e.g., 31" or 33"), round to the nearest even number. For cup sizes, if you're between sizes, try both and see which fits better. Different brands may fit differently, so always try on when possible. Our bra calculator will give you the closest size, but you may need to try sister sizes.
How do you measure your bra size if you're between cup sizes?
If our bra calculator shows you're between cup sizes, try both sizes. For example, if you're between a C and D cup, try both 34C and 34D. The size that provides the best fit without gaping or spilling is your correct size. Remember, different bra styles may fit differently even in the same size.
Will this calculator work for UK brands like M&S?
Yes, our UK bra calculator uses standard UK sizing with double letters (DD, FF, GG, etc.), which is the same system used by most UK brands including M&S (Marks & Spencer). The results should work well for UK brands, though individual bra styles may fit slightly differently. Always try on bras when possible to ensure the best fit.
How accurate is this bra size calculator UK?
Our bra calculator UK is based on standard UK sizing measurements used by professional fitters. However, bra sizing can vary slightly between brands and styles. Use our calculator as a starting point, then try on bras in that size and adjust as needed. The calculator is most accurate when measurements are taken correctly - standing straight, with the tape level and snug but not tight.
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