To create a bra size conversion tool, we would need a size chart that includes different bra size systems (like US, UK, EU, FR, etc.) and their corresponding measurements. Here is a common bra size conversion chart for reference:

Bra Size Conversion Chart

US/Canada	UK	EU	FR/BE	IT	AU/NZ
30A	30A	65A	85A	1A	8A
30B	30B	65B	85B	1B	8B
30C	30C	65C	85C	1C	8C
30D	30D	65D	85D	1D	8D
32A	32A	70A	90A	2A	10A
32B	32B	70B	90B	2B	10B
32C	32C	70C	90C	2C	10C
32D	32D	70D	90D	2D	10D
34A	34A	75A	95A	3A	12A
34B	34B	75B	95B	3B	12B
34C	34C	75C	95C	3C	12C
34D	34D	75D	95D	3D	12D
36A	36A	80A	100A	4A	14A
36B	36B	80B	100B	4B	14B
36C	36C	80C	100C	4C	14C
36D	36D	80D	100D	4D	14D
38A	38A	85A	105A	5A	16A
38B	38B	85B	105B	5B	16B
38C	38C	85C	105C	5C	16C
38D	38D	85D	105D	5D	16D

How to Use the Conversion Tool

You can provide a specific bra size, and based on this chart, I can convert it to other sizing systems for you.

For example:

• If you have a US size 34B, I can convert it to the UK, EU, FR, and AU sizes using the conversion chart.

Let me know if you’d like a specific size converted, or if you’d like to build a more interactive tool! I can also guide you through calculating or converting a particular bra size based on measurements (underbust and bust measurements).

Calculate Your Cup Size

• Subtract your band size from your bust size.
• The difference between these measurements determines your cup size.

Difference (in inches)	Cup Size
1 inch	A
2 inches	B
3 inches	C
4 inches	D
5 inches	DD/E
6 inches	DDD/F
7 inches	G

Bra Size Formula:

• Bra size = Band Size + Cup Size
  • For example, if your band size is 34 inches and your bust measurement is 37 inches, the difference is 3 inches, which corresponds to a C cup. Therefore, your bra size is 34C.

Example of a Bra Size Chart:

Band Size (inches)	Under Bust Measurement (inches)	Bust Measurement (inches)	Cup Size	Bra Size
28	26-28	28-29	A	28A
30	28-30	30-31	B	30B
32	30-32	32-33	C	32C
34	32-34	34-35	D	34D
36	34-36	36-37	DD/E	36DD/E
38	36-38	38-39	DDD/F	38DDD/F
40	38-40	40-41	G	40G

International Size Conversion:

Bra sizing can vary by country. Here’s a general guide to converting sizes internationally:

US Size	UK Size	EU Size	FR Size	AUS Size
34B	34B	75B	90B	12B
36C	36C	80C	95C	14C
38D	38D	85D	100D	16D
40DD	40DD	90DD	105DD	18DD

Additional Bra Sizing Tips:

• Band size may need to be adjusted depending on the brand, as some bras may fit differently.
• If your band size feels too tight or too loose, try adjusting by going up or down a size.
• Cup size is just as important as band size, so try to focus on both for the best fit.
• Sister sizing: If one size doesn’t fit well, you can try a sister size. For example, if you usually wear a 34B and it’s too tight, you could try a 36A or 32C. These sizes will adjust the fit while maintaining the same cup volume.

Bra Fit Test:

• The band should be snug but comfortable. It should stay in place when you raise your arms, and the straps should not bear the full weight of your breasts.
• The cups should fully cover your breasts without any spillage or gaping.
• The straps should stay in place without digging into your shoulders.