Find your perfect fit with our advanced bra sizing tool and comprehensive fit analysis
Enter your measurements for accurate bra size calculation
Measure snugly around your torso, directly under your bust
Measure around the fullest part of your bust while wearing a well-fitted bra
Band Size: Measure around your ribcage, directly under your bust. Keep the tape level and snug but not tight.
Bust Size: Measure around the fullest part of your bust while wearing a well-fitted, non-padded bra.
Tips: Stand straight, breathe normally, and round measurements to the nearest ¼ inch or ½ cm for best results.
The most comprehensive resource for finding your perfect bra fit
Research from the University of Portsmouth reveals that 85% of women wear incorrectly fitted bras, with 70% wearing bands too large and 10% wearing cups too small. This widespread issue contributes to chronic back pain, poor posture, breast pain, and reduced self-confidence. A properly fitted bra distributes breast weight evenly, reducing strain on the neck, shoulders, and spine.
The Cooper's ligaments, which provide natural breast support, can stretch permanently when not properly supported by a well-fitted bra. This emphasizes the critical importance of wearing the correct size throughout your lifetime. Professional bra fitters report that finding the right size can improve a woman's perceived body image by up to 40% and increase daily comfort significantly.
Medical professionals recommend professional fittings every 6-12 months, as breast size can fluctuate due to hormonal changes, weight fluctuations, pregnancy, aging, and medication effects. Our calculator uses the most current industry standards and international sizing conventions to provide accurate starting measurements for your bra fitting journey.
The band measurement is the foundation of proper bra fit and should provide 80% of the bra's support. This measurement determines your band size and is critical for overall fit and comfort.
Pro Tip: Take this measurement 3 times and use the average. The band should feel secure but allow comfortable breathing and movement.
The bust measurement determines your cup size when compared to the band measurement. This measurement should capture the fullest part of your bust for accurate cup sizing.
Important: The difference between bust and band measurements determines your cup size. Each inch of difference typically equals one cup size.
| Inches | CM | US/UK | EU/FR | IT | AU/NZ | JP |
|---|---|---|---|---|---|---|
| 26 | 66 | 26 | 55 | -1 | 4 | 60 |
| 28 | 71 | 28 | 60 | 0 | 6 | 65 |
| 30 | 76 | 30 | 65 | 1 | 8 | 70 |
| 32 | 81 | 32 | 70 | 2 | 10 | 75 |
| 34 | 86 | 34 | 75 | 3 | 12 | 80 |
| 36 | 91 | 36 | 80 | 4 | 14 | 85 |
| 38 | 97 | 38 | 85 | 5 | 16 | 90 |
| 40 | 102 | 40 | 90 | 6 | 18 | 95 |
| Difference | US Cup | UK Cup |
|---|---|---|
| 1" | A | A |
| 2" | B | B |
| 3" | C | C |
| 4" | D | D |
| 5" | DD/E | DD |
| 6" | DDD/F | E |
| 7" | G | F |
| 8" | H | FF |
EU/French: Uses double letters differently than UK (e.g., DD becomes E)
Italian: Numerical system (1-12) with some letter combinations
German: Similar to EU but may vary by manufacturer
Note: Always check manufacturer-specific size charts as European brands can vary significantly in their sizing standards.
Sister sizes have the same cup volume but different band-to-cup ratios. Use these when your exact size isn't available.
| Smaller Band | True Size | Larger Band |
|---|---|---|
| 30C | 32B | 34A |
| 30D | 32C | 34B |
| 32D | 34C | 36B |
| 32DD | 34D | 36C |
| 34DD | 36D | 38C |
| 34DDD | 36DD | 38D |
Shallow
Breast tissue spreads wide across chest with minimal forward projection
Average
Moderate projection with balanced width and depth
Projected
Significant forward projection from chest wall
Narrow
Breast base extends less than 5" across chest
Average
Breast base spans 5-6" across chest
Wide
Breast base extends 6"+ and may wrap toward underarms
Full on Top
More tissue above nipple line (2/5, 2/6 shape)
Even Fullness
Equal distribution above and below nipple (2/4 shape)
Full on Bottom
More tissue below nipple line (1/4, 1/5 shape)
Common Issue: 65% of women have noticeable asymmetry (½ cup or more difference)
Fitting Strategy: Fit to larger breast, use padding/inserts for smaller side
Recommended Styles: Contour cups, T-shirt bras, adjustable padding systems
Professional Tip: Consider custom-fitted bras for significant differences (2+ cup sizes)
Mastectomy: Specialized post-mastectomy bras with pockets for prosthetics
Reduction: Allow 6-12 months for final shape, frequent re-measuring needed
Augmentation: Consider implant placement (over/under muscle) affects fit
Medical Consultation: Always consult certified fitters and medical professionals
Growth Pattern: Average 1-3 cup size increases, band may increase 2-6 inches
Timing: Re-measure every 6-8 weeks during pregnancy
Nursing Phase: Size fluctuates daily, consider nursing bras in final trimester
Investment Strategy: Buy 2-3 well-fitting bras per stage vs. many cheaper options
Hormonal Changes: Menopause can cause size/shape changes
Skin Elasticity: May require different support levels and styles
Comfort Focus: Prioritize wider straps, softer materials, wireless options
Re-fitting Schedule: Annual professional fittings recommended after age 40
Best For: Daily wear, fitted clothing, professional settings
Features: Seamless cups, light padding, smooth under clothes
Body Types: All shapes, especially shallow to average projection
Avoid If: Very projected shape, seeking maximum lift
Best For: Larger busts (D+ cups), conservative coverage
Features: Higher neckline, wider straps, full encasement
Body Types: Full on top, even fullness, wide root width
Benefits: Maximum support, reduces apparent size, comfort
Best For: Low-cut tops, creating cleavage, evening wear
Features: Low-cut cups, wide-set straps, horizontal seaming
Body Types: Full on bottom, even fullness, shorter torsos
Styling: Creates lifted, separated silhouette
Best For: Special occasions, deep V-necks, enhancing cleavage
Features: Heavy padding, angled cups, center gore may not tack
Body Types: Smaller busts (A-C cups), full on bottom shapes
Note: Prioritize occasion wear over daily comfort
Best For: Comfort, lounging, light activity, smaller busts
Features: No underwire, soft cups, pull-on or light closure
Body Types: A-C cups, self-supporting breasts
Benefits: Maximum comfort, natural shape, minimal structure
Best For: Exercise, high-impact activities, athletic wear
Features: Compression or encapsulation, moisture-wicking fabrics
Support Levels: Light (yoga), Medium (gym), High (running)
Sizing: May run smaller; consider going up a band size
Hand Washing (Preferred): Use lukewarm water and gentle lingerie detergent
Machine Washing: Use lingerie bag, gentle cycle, cold water only
Frequency: After 2-3 wears for daily bras, immediately for sports bras
Drying: Air dry flat or hang by center gore (never by straps)
Molded Cups: Stack or nest cups to maintain shape
Soft Cups: Lay flat in drawer or fold along center seam only
Travel: Use dedicated bra travel cases or pack in shoes
Rotation: Allow 24-48 hours between wears for elastic recovery
Band Issues: Rides up, stretches beyond comfort on loosest hooks
Cup Problems: Wrinkling, gaping, or spillage that wasn't present initially
Strap Concerns: Digging in, slipping, or losing elasticity
General Timeline: 6-12 months for daily wear bras with proper care
Underwire Poking: Usually indicates worn fabric or wrong size
Strap Marks: Band likely too loose, straps compensating for support
Center Gore Floating: Cup too small or wrong shape for breast type
Back Bulge: Band too tight or cups too small pushing tissue back
Expert answers to the most common bra fitting questions and concerns
Re-measure every 6-12 months or after significant changes: 10+ pound weight fluctuation, pregnancy, hormonal changes, or medication that affects body composition. Your size can also fluctuate during your menstrual cycle (up to ½ cup difference). Professional fitters recommend checking annually after age 30, and every 6 months after major life events.
Pro tip: Keep a sizing journal noting date, measurements, and any life changes for patterns.
For band sizes: choose the smaller size for better support (bands stretch over time). For cup sizes: go larger to prevent spillage and discomfort. Sister sizes are your best friend - same cup volume, different band fit. If measuring 33", try both 32 and 34 bands with appropriate sister cup sizes.
Remember: A well-fitted band should feel snug on the loosest hook when new.
Bra sizing lacks global standardization. European brands often run 1-2 sizes smaller than US brands. UK brands are generally true to size but use different cup progressions (DD vs E). Manufacturing variations, target demographics, and design philosophies all affect fit. Always check brand-specific size charts and read customer reviews.
Keep a fitting notes app with your size in different brands for future reference.
A perfect fit should feel like a gentle hug - secure but not restrictive. The band should sit level and provide 80% of support. You should be able to slide 1-2 fingers under the band. Cups should fully contain breast tissue without gaps or spillage. The center gore should lay flat against your sternum. Straps should stay in place without digging in.
If you're constantly adjusting your bra, it doesn't fit properly.
65% of women have noticeable breast asymmetry (½+ cup difference). Always fit to your larger breast and use padding, inserts, or "cookies" for the smaller side. Contour cup bras work best as they're forgiving. For significant differences (2+ cup sizes), consider custom fittings or brands specializing in asymmetry solutions.
Asymmetry is completely normal - don't let it discourage you from finding great-fitting bras.
Yes! Sports bras often run smaller and prioritize compression over comfort. You may need to go up a band size or down a cup size. Encapsulation sports bras (individual cups) fit more like regular bras. Compression styles (uni-boob effect) size more like athletic wear. Check if the brand uses traditional sizing (32C) or simplified sizing (S/M/L).
High-impact activities may require going up a size for maximum security and comfort.
Get professionally fitted if you've never been measured, are unsure about your size, have specific fit challenges, or need specialty bras (post-surgery, maternity, etc.). Good times: before major bra purchases, after weight/body changes, or if you're consistently uncomfortable in bras. Look for certified fitters at specialty lingerie boutiques rather than department stores.
A good professional fitting is an investment that pays off in comfort and confidence.
Replace bras when: the band rides up (even on tightest hook), cups gap or wrinkle, underwire pokes through fabric, straps constantly slip or dig in, or the bra no longer provides adequate support. With proper care and rotation, quality bras last 6-12 months. Daily wear bras need replacing sooner than occasion-only pieces.
Invest in 3-5 good bras rather than 10+ poor-quality ones for better value and fit.
A riding-up band indicates the band is too large. The band should provide 80% of bra support, not the straps. Try going down a band size and up a cup size (sister sizing). Also check that you're wearing the bra correctly - the band should sit parallel to the floor, not angled upward in back.
If you need the loosest hook when the bra is new, the band is definitely too large.
A floating center gore usually means the cups are too small, pushing the gore away from your chest. It can also indicate the wrong bra style for your breast shape (too narrow wires for wide-set breasts, or plunge style when you need more center support). Try going up a cup size or choosing a different style with a higher center gore.
The center gore should tack (lie flat) against your sternum for proper support and separation.
Some minor issues can be addressed: strap slipping (tighten or use strap clips), minor gapping (contour pads or different style), slight asymmetry (padding inserts). However, major fit issues (wrong band/cup size, significant shape mismatch) require different sized or styled bras. Don't compromise on fit for the sake of a particular bra.
When in doubt, professional alterations are possible but often cost more than buying the right size.
Quality bras ($50-150+) typically offer better construction, longer-lasting materials, superior fit, and more size options. They're especially worthwhile for daily-wear bras and if you have fitting challenges. However, fit matters more than price - a well-fitting $30 bra beats a poor-fitting $200 bra. Invest wisely in styles you'll wear frequently.
Cost per wear makes quality bras economical - a $100 bra worn 100 times costs $1 per wear.
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