Bikini Calculator

Shopping for swimwear can be a challenging experience, as sizing can vary dramatically between brands. A bikini that fits perfectly provides comfort and confidence, whether you're at the beach or by the pool. The Bikini Calculator is a helpful tool designed to give you an estimated top and bottom size based on your body measurements. By using your bust, underbust, waist, and hip measurements, this calculator simplifies the process of finding a size that's right for you.

How to Use the Bikini Calculator

To get your estimated bikini size, you'll need a flexible measuring tape and your measurements in inches. Follow these steps:

1. Measure Your Bust: Wrap the measuring tape around the fullest part of your bust. Keep the tape level and not too tight. Enter this value in the "Bust" field.
2. Measure Your Underbust: Measure around your ribcage, directly underneath your bust. This is your band size. Enter it into the "Underbust" field.
3. Measure Your Waist: Measure around the narrowest part of your torso, typically just above your belly button. This is your natural waistline.
4. Measure Your Hips: Wrap the tape around the fullest part of your hips and bottom.
5. Get Your Results: The calculator will provide an estimated size for your bikini top (e.g., S, M, L) and your bikini bottom.

The Sizing Logic Explained

Bikini sizing is not standardized, but most brands use a system based on general measurements. Our calculator uses a simplified, common logic to provide a starting point.

Top Size Calculation

Bikini top sizes are often determined by the difference between your bust and underbust measurement, which relates to cup size.

Cup Difference = Bust Measurement - Underbust Measurement

• XS: ~1 inch difference
• S: ~2 inches difference
• M: ~3 inches difference
• L: ~4 inches difference
• XL: ~5+ inches difference

Bottom Size Calculation

Bikini bottom sizes are typically based on your hip measurement, though waist can also be a factor.

• XS: Hips < 34"
• S: Hips 34" - 37"
• M: Hips 37" - 40"
• L: Hips 40" - 43"
• XL: Hips > 43"

Practical Example

Let's see how it works for someone with the following measurements:

• Bust: 36 inches
• Underbust: 30 inches
• Waist: 28 inches
• Hips: 38 inches

Top Size Calculation:

Cup Difference = 36 (Bust) - 30 (Underbust) = 6 inches

A 6-inch difference corresponds to a larger cup size, so the calculator would suggest a size XL for the top to ensure adequate coverage.

Bottom Size Calculation:

The hip measurement is 38 inches. Based on the sizing chart, this falls squarely within the Medium (M) range.

Therefore, this person's estimated size would be an XL top and an M bottom. This highlights a common issue where top and bottom sizes differ, making mix-and-match bikini sets a great option.

Why Accurate Measurements Matter

Taking the time to measure yourself accurately can make all the difference in finding swimwear that you feel good in. A well-fitting bikini top provides proper support, while correctly sized bottoms prevent uncomfortable digging or slipping. While this calculator is a great starting point, remember that fit can also be affected by the style of the bikini, the fabric, and the brand's unique sizing model.

For more specific sizing, our Bra Size Calculator can provide a more detailed band and cup size, which is useful for underwire bikini tops. Similarly, understanding your general clothing size with a Dress Size Calculator can offer additional context.

When in doubt, always consult the specific size chart provided by the swimwear brand. Reputable retailers like Bare Necessities offer detailed fitting guides. For style inspiration, fashion magazines like Vogue showcase the latest trends in swimwear.

If you're creating your own swimwear, our Fabric Calculator can help you determine how much material you'll need.

Frequently Asked Questions (FAQ)

What if I'm between sizes?

If you're between sizes, consider the style and coverage you prefer. For less coverage, you might size down. For more coverage and a more secure fit, it's usually best to size up.

Does this calculator work for one-piece swimsuits?

It can provide a good estimate. For one-piece swimsuits, the most important measurement is often your torso length, in addition to bust, waist, and hips. It's best to use the brand's size chart and focus on the largest of your measurements to determine the size.

How often should I re-measure myself?

Bodies change, so it's a good idea to take new measurements each swim season or before purchasing new swimwear to ensure the best fit.