Butt Shape Types — The Five Common Glute Shapes Explained

Your Shape Is Not a Choice

Before we get into the five types, let's be clear about something: your butt shape is primarily determined by factors you didn't choose — your skeletal structure, your genetic fat distribution pattern, and the insertion points of your gluteal muscles on the pelvis.

Understanding your natural shape isn't about labelling or limiting yourself. It's about having realistic expectations for what training and nutrition can achieve, and recognising that shape diversity is a biological reality, not a flaw to be corrected.

What Determines Butt Shape?

1. Pelvic Structure

The width, tilt, and orientation of your pelvis create the bony framework your glutes sit on. A wider pelvis creates a broader gluteal base. Anterior pelvic tilt increases apparent gluteal projection, while posterior tilt flattens it. You cannot change your pelvic structure through exercise.

2. Fat Distribution

Where your body preferentially stores subcutaneous fat is largely genetically determined and hormonally influenced. Oestrogen promotes gluteofemoral fat storage, which is why buttock shape often changes during puberty, pregnancy, and menopause. You can change your total body fat percentage, but you have very limited control over where fat comes off or goes on.

3. Muscle Architecture

The gluteus maximus is a single large muscle, but its fibre orientation and insertion points vary between individuals. You can increase gluteal muscle size through resistance training, but the shape of the muscle — its origin, insertion, and fibre angle — is genetically fixed.

The Five Common Butt Shapes

1. Round (O-Shape)

What it looks like: Full, evenly distributed volume with a smooth, curved profile from all angles.

What causes it: Even fat distribution across the gluteal region, combined with moderate to high muscle mass and a pelvis that positions the glutes prominently. More common in women with higher oestrogen levels.

Frequency: Roughly 20–25% of women. Despite being the most "idealised" shape in current Western media, it's actually not the most common natural shape.

Training considerations: Round shapes respond well to general glute training. Fat gain tends to be proportional, so overall body fat management is the key variable.

2. Square (H-Shape)

What it looks like: The widest point of the hips is at roughly the same level as the waist, creating a more angular, boxy silhouette.

What causes it: A wider iliac crest, less anterior pelvic tilt, and a fat distribution pattern that favours the area around the hip bones. Very common in athletic and mesomorphic body types.

Frequency: Approximately 25–30% of women, making it one of the most common shapes.

Training considerations: Targeted gluteal hypertrophy (especially gluteus medius and upper glute work) can add more roundness and projection. However, the underlying skeletal width won't change.

3. Heart / A-Shape (Pear)

What it looks like: Narrower at the top, widening toward the lower buttock and upper thigh.

What causes it: Fat deposits concentrated in the lower gluteal and upper thigh area. Strongly associated with high oestrogen levels.

Frequency: Approximately 20–25% of women.

Training considerations: Upper glute development (hip thrusts, glute bridges with abduction) can help balance the shape by adding volume to the upper gluteal region.

4. V-Shape (Inverted Triangle)

What it looks like: Wider at the top near the waist, narrowing toward the gluteal fold. The lower buttock may appear less full.

What causes it: Lower oestrogen levels, which reduce gluteofemoral fat storage. More common post-menopause.

Frequency: Approximately 15–20% of women, increasing with age.

Training considerations: Lower glute development (deep squats, Romanian deadlifts, step-ups) can add volume to the under-filled lower region.

5. Asymmetric / Combination

What it looks like: Different shapes or volumes on the left and right sides, or a blend of two or more of the above categories.

What causes it: This is the norm, not the exception. Subtle pelvic asymmetry, dominant-leg differences, habitual postural patterns, and mild scoliosis all contribute. A 2015 study found that over 80% of women had measurable gluteal asymmetry.

Training considerations: Unilateral exercises (single-leg hip thrusts, Bulgarian split squats, single-leg deadlifts) can help reduce muscle-based asymmetry.

Can You Change Your Butt Shape?

The honest answer is: partially.

What training can change:

• Gluteal muscle size (hypertrophy) — significant changes are possible
• Muscle tone and definition
• The degree of gluteal projection
• Minor asymmetry driven by muscle imbalances

What training cannot change:

• Pelvic width and structure
• The origin and insertion points of your gluteal muscles
• Where your body preferentially stores and loses fat
• Fundamental skeletal proportions

The Takeaway

There is no "best" butt shape. Round shapes dominate current Western aesthetics, but beauty standards are cultural constructions that shift every decade. Research consistently shows that perceived attractiveness is driven more by proportion, confidence, and overall health than by any specific shape.

Understanding your shape helps you set realistic goals, choose effective training approaches, and stop comparing yourself to people whose genetics built them a fundamentally different body.

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