Breast Size Calculator: Measure Bust, Volume & Fit in Minutes

Table of Contents

• Why use the breast size calculator
• How to capture accurate breast measurements
• Using the breast size calculator step-by-step
• Make the results work for you
• Breast size calculator FAQ

Why use the breast size calculator

Our breast size calculator extends the core bra size tool so you can record bust measurements, view estimated volume, and translate your results into multiple systems without leaving the page.

How to capture accurate breast measurements

Before you type any numbers, tidy up the measurements that power the calculator. Consistent inputs deliver consistent recommendations.

1. Use a soft measuring tape and take a snug underbust measurement while you exhale.
2. Measure the fullest part of your bust—standing, leaning, and lying readings give the calculator more context.
3. Log the units you use. Centimeters or inches both work, but stay consistent throughout the session.
4. Repeat each measurement at least twice and write it down. Small changes in tape tension affect the final cup volume.

Using the breast size calculator step-by-step

When the measurements are ready, open the calculator panel and follow these steps to map both bra and breast size.

• Enter snug underbust and bust values, then toggle between basic and advanced modes to add leaning or lying measurements.
• Switch between centimeters and inches at any time—the calculator instantly recalculates cup depth and international labels.
• Send the primary result to the brand converter to compare how different labels express the same breast volume.
• Copy the summary so you can paste measurements into fit notes, medical records, or future fittings.

Make the results work for you

With the core result saved, tailor the insights to match your goals.

• Track breast volume changes over time by repeating the calculator monthly or after life events such as pregnancy or training cycles.
• Test sister sizes to see how the same cup volume behaves on tighter or looser bands, then note which combination stabilises your bust best.
• Pair the calculator with our sports support lab and breast weight calculator to select fabrics, straps, and impact levels that respect your measurements.

Breast size calculator FAQ