Q: I don't have a tape measure. What now?

Try the AI Smart Fit Calculator - it estimates your size from your dress size and how your current bra feels.

Question 1

Is the bra size calculator actually free?

Accepted Answer

Yes. Every calculator on this site is free, with no signup and no hidden tier. That's not changing.

Question 2

Do you store my measurements?

Accepted Answer

No. Every calculator runs in your browser using JavaScript. Your numbers never leave your device or reach our servers.

Question 3

How accurate is the main calculator?

Accepted Answer

It uses the standard band-and-cup method fitters have relied on for decades. It's an estimate based on two measurements. Accurate for most people, but brand cuts vary, so treat the result as a strong starting point, not a guarantee.

Question 4

Why did I get a different size here than at another calculator?

Accepted Answer

Different sites use different rounding rules for the band. We use the modern method (round up to the nearest even inch) instead of the older +4 method. See Our fitting process for the exact math.

Question 5

What's a sister size?

Accepted Answer

A sister size is a different band/cup combination that holds roughly the same cup volume. Going up one band size and down one cup letter (or the reverse) usually fits similarly. Try the Sister Size Calculator.

Question 6

I don't have a tape measure. What now?

Accepted Answer

Try the AI Smart Fit Calculator- it estimates your size from your dress size and how your current bra feels.

Question 7

Why do you have separate calculators for teens, seniors, and postpartum?

Accepted Answer

Because the same two measurements mean slightly different things depending on your situation. A teen's body is still changing, postpartum sizing shifts week to week, and older skin/tissue changes affect fit. Each version gives fit notes suited to that stage.

Question 8

Do the country calculators use different math?

Accepted Answer

The underlying measurement is the same. Only the band/cup labels differ by country. See Global Size Converter to convert your size to any of 7 systems at once.

Question 9

Who is Claire Bennett?

Accepted Answer

Claire spent 10+ years hand-fitting women in specialty lingerie boutiques before building this site. She's not a doctor or clinician. She writes from real fitting-room experience. Read more on the About page.

Question 10

Is this medical advice?

Accepted Answer

No. These tools are for fit and shopping guidance only. See our full Disclaimer.

Question 11

Why does my size feel different from brand to brand?

Accepted Answer

Cut, fabric stretch, and each brand's own size chart all shift the fit. Try the Brand Size Decoder for a starting point at specific retailers.

Question 12

How often should I get remeasured?

Accepted Answer

Weight changes, pregnancy, and even a new season of exercise can shift your size. A quick remeasure every 6-12 months (or after a major body change) keeps you accurate.

Question 13

Can I use these calculators for a bra without underwire?

Accepted Answer

Yes. The band and cup measurements work the same way regardless of underwire. Just size based on your closest supportive band.

Question 14

Do you sell bras?

Accepted Answer

No. This site is calculators and education only. Our Best Bras guides link out to retailers, but we don't sell anything ourselves.

Question 15

Why is there no app yet?

Accepted Answer

It's on the roadmap: see Get the App for the honest status.

Question 16

What if my band and cup feel right but the bra still doesn't sit well?

Accepted Answer

That's usually a shape or style issue, not a size issue. Check Fit Problems for the specific symptom.

Question 17

Is my data shared with advertisers?

Accepted Answer

The calculators themselves send nothing anywhere. See our Privacy Policy for the full picture, including standard hosting logs.

Question 18

Can I suggest a calculator or guide you're missing?

Accepted Answer

Yes. Email us at hello@bra-sizecalculator.com. Reader requests have shaped a lot of what's on this site.

Frequently Asked Questions

Frequently Asked Questions