Yes, the A Bra That Fits calculator is highly accurate for most people. Unlike traditional calculators that use only 2 measurements and often add 4 inches to the band (an outdated practice), the ABTF method uses 6 measurements to account for:

• Tissue softness and compressibility
• Breast projection
• Natural shape variations
• Individual ribcage flexibility

Over 2 million Reddit users have found their true size using this method, with most reporting dramatic improvements in comfort and fit.

If your calculated size doesn't feel right, there are several things to consider:

• Measurement errors: Double-check that all 6 measurements were taken correctly. The tape should be level and measurements should be honest (not too tight or loose).
• Shape mismatch: Even with the right size, the wrong bra style for your shape will fit poorly. Use the shape guide to find compatible styles.
• Brand variation: Try sister sizes, as brands size differently. UK brands tend to run true to size; US brands often run small in cups.
• Sticker shock: Many people are surprised by their calculated size (especially larger cups). Trust the measurements and try the size before dismissing it.

The r/ABraThatFits subreddit community is extremely helpful for fit checks and troubleshooting.

The r/ABraThatFits method was developed by the Reddit community after years of research and thousands of fit assessments. Key principles include:

• 6 measurements: Loose, snug, and tight underbust; standing, leaning, and lying bust
• No "+4" method: Unlike department stores, ABTF doesn't add inches to your band measurement
• Shape matters: Size alone doesn't guarantee fit; breast shape determines which styles work
• Sister sizes: Understanding cup volume helps find alternatives when exact sizes aren't available
• Community support: The subreddit provides fit checks, brand recommendations, and troubleshooting

Finding a well-fitting bra is challenging for most women due to several factors:

• Wrong size: Studies show 80% of women wear the wrong size, often because of outdated fitting methods
• Limited size ranges: Most stores only carry 32A-38DD, while many women need sizes outside this range
• Ignoring shape: Two people with the same size can have completely different shapes requiring different styles
• Brand inconsistency: A 34D varies significantly across brands
• Poor fitting advice: Department store fitters often use the "+4" method which adds 4 inches to your band, resulting in loose bands and small cups

The solution: Use this calculator to find your true size, identify your shape, and shop from brands that carry your size (often online specialty retailers).

For accurate results, take these 6 measurements while wearing a non-padded bra or no bra:

1. Loose Underbust: Comfortable, like you'd wear a t-shirt. The tape should be snug but you can slide a finger underneath.
2. Snug Underbust: As tight as you'd want a bra band. Firm but not uncomfortable.
3. Tight Underbust: As tight as possible while exhaling fully. This shows your minimum measurement.
4. Standing Bust: Stand straight, measure around the fullest part of your bust.
5. Leaning Bust: Bend forward at 90° (back parallel to floor), measure around the fullest point as breasts hang.
6. Lying Bust: Lie flat on your back, measure around the fullest part.

Tip: Use a soft measuring tape and keep it level (parallel to the floor) for all measurements.

Sister sizes are bra sizes that share the same cup volume but have different band sizes. When you go down a band size, you go up a cup size (and vice versa) to maintain equivalent cup volume.

Example: 34D, 32DD, and 36C are all sister sizes with the same cup volume.

When to use sister sizes:

• A brand runs small/large in the band
• Your exact size is unavailable
• You're between band sizes
• You prefer a firmer (smaller band) or looser (larger band) fit

Our calculator automatically shows your sister sizes along with your primary recommendation.

The shape guide helps identify four key characteristics that affect bra fit:

• Fullness: Is your tissue mostly above (FOT), below (FOB), or evenly distributed around your nipple?
• Projection: How far do your breasts project from your chest wall? Shallow breasts spread wide; projected breasts extend forward.
• Root Width: How wide does your breast tissue extend across your chest?
• Spacing: How close together or far apart are your breasts?

Each characteristic narrows down which bra styles will work for you. For example, someone with projected, full-on-bottom breasts needs different styles than someone with shallow, full-on-top breasts.

Yes! The A Bra That Fits calculator includes an option for people assigned male at birth (AMAB). When selected, the calculator adjusts its algorithm to account for:

• Different ribcage shapes (typically wider and more barrel-shaped)
• Different tissue distribution patterns
• Potentially different projection characteristics

The r/ABraThatFits community is welcoming and supportive of all people seeking well-fitting bras, regardless of gender identity or body type.

If your size falls outside the typical 32A-38DD range found in most stores, here are great options:

• Online retailers: Bare Necessities, Bravissimo, Breakout Bras, Amazon (check reviews)
• UK brands: Panache, Freya, Curvy Kate, Fantasie (known for consistent sizing and wide range)
• Polish brands: Ewa Michalak, Comexim (excellent for projected shapes)
• Specialty boutiques: Search for "bra fitting boutique" in your area
• Nordstrom: Carries extended sizes and offers free shipping/returns

Tip: Order from places with free returns so you can try multiple sizes and styles without financial risk.

Here are the most common fit issues and their solutions:

• Band rides up in back: Band is too loose. Try a smaller band size.
• Straps fall down: Band is too big or straps are set too wide for your shoulders.
• Cups overflow/quad boob: Cups are too small. Go up a cup size.
• Cups wrinkle or gap: Cups are too big or the wrong shape. Try smaller cups or different styles.
• Gore doesn't lay flat: Cups are too small, or the bra style doesn't match your shape.
• Underwire sits on tissue: Cup is too small or too shallow. Try bigger cups or more projected styles.
• Underwire pokes at sides: Wires are too wide for your root width. Try narrower wires.