How the Bikini Calculator works
This tool estimates your body shape from three measurements — bust, waist, and hip circumference — using the same rule-based comparisons found in common swimwear and clothing-fit guides. It then suggests a bikini style category that tends to flatter that shape.
The classification rules
- Hourglass: bust and hips are within about 1 inch (2.5 cm) of each other, and the waist is at least 25% narrower than the bust.
- Pear (triangle): hips exceed the bust by 3.6 inches (9 cm) or more, and the waist is at least 15% narrower than the hips.
- Inverted triangle: the bust exceeds the hips by 3.6 inches (9 cm) or more, and the waist is at least 15% narrower than the bust.
- Apple (round): the waist is at least 90% as wide as both the bust and the hips — little difference between the three.
- Rectangle (straight): bust, waist, and hips are all close in width and none of the above conditions apply.
Alongside the shape label, the calculator reports your waist-to-hip ratio (waist ÷ hip) and the raw bust-hip difference, so you can see the numbers behind the classification rather than just the result.
How to measure correctly
- Bust: wrap the tape around the fullest part of your chest, keeping it level and snug but not tight.
- Waist: measure at the narrowest point of your torso, usually just above the belly button.
- Hip: measure around the widest part of your hips and buttocks.
Measure in your underwear or close-fitting clothing, keep the tape parallel to the floor, and take each measurement two or three times to average out small errors.
Frequently Asked Questions
What does the Bikini Calculator actually measure?
It compares your bust, waist, and hip circumferences using a standard set of ratio rules to classify your figure into one of five common shape categories — hourglass, pear, apple, rectangle, or inverted triangle — then suggests a bikini style that typically flatters that shape.
How do I measure bust, waist, and hip correctly?
Measure bust around the fullest part of your chest, waist at the narrowest point of your torso (usually just above the belly button), and hips around the widest part of your hips and buttocks. Keep the tape level and snug but not tight, and measure in your underwear or close-fitting clothing for the most accurate numbers.
What is the waist-to-hip ratio (WHR) shown in the results?
WHR is simply your waist circumference divided by your hip circumference. Here it is used only as one input to the body-shape classification and style suggestion — it is not a health or fitness score.
Is the suggested bikini style a strict rule?
No. The style suggestion reflects common styling guidance for each shape category, not a rule you must follow. Personal preference, fabric, and how a suit actually fits your body matter more than any calculator label.