The inverted triangle measurement pattern
The calculator returns Inverted Triangle when the bust is at least 3.6 in (9.1 cm) larger than the hips, and the waist is not close enough to both measurements to count as Apple.
When the waist is also at least 9 in (22.9 cm) smaller than the bust, the result includes a note that some systems call this a “top hourglass.”
How the classification works
The calculator checks five rules in a fixed order — Apple, Hourglass, Pear, Inverted Triangle, then Rectangle — and returns the first one your measurements meet. The thresholds compare your measurements with each other, so your overall size does not affect the result. After classifying, it also tests whether a change of about 1 in (2.5 cm) in any single measurement would give a different shape, and tells you if so.
You can see every rule side by side on the body shape types overview.
Measurement examples
These examples show how specific numbers are classified, including a near miss for comparison.
Bust versus shoulders
Many style guides describe inverted triangles as having broad shoulders. This calculator does not measure the shoulders. It uses the bust circumference as the upper-body measurement, following the FFIT approach, which classifies shapes from circumferences rather than shoulder width.
That means a person with broad shoulders and a smaller bust may get a Rectangle or Hourglass result here, while a guide based on shoulder width might call them an inverted triangle. Neither is wrong — they measure different things.
Why a shoulder field was left out
Shoulder measurements are hard to take consistently at home. Shoulder width is measured across the back from one shoulder point to the other, and those points are hard to find on yourself. Shoulder circumference depends heavily on arm position.
Research assessing FFIT has also noted that it does not use shoulder measurements. Rather than add a field with an untested threshold, this calculator states the limitation clearly.
Inverted triangle and top hourglass
If your bust is much larger than your hips and your waist is also well defined, you may see your shape called a top hourglass elsewhere. This calculator groups both under Inverted Triangle and adds a note when the waist is defined enough for the sub-type.
Common misconceptions
- “Inverted triangle always means broad shoulders.” In measurement-based systems like this one, the classification comes from bust and hips. Shoulder width is not part of the rule.
- “This shape only describes athletic bodies.” An upper-body-dominant pattern can come from skeletal frame, bust size, muscle, or a combination. The label says nothing about fitness.
- “The bust measurement is the same as bra size.” Bra sizes combine band and cup measurements in brand-specific ways. The calculator uses a single tape measurement around the fullest part of the bust.