How to Measure Yourself and Choose a Sewing Pattern Size

The single most common mistake made by new sewists is picking a sewing pattern size based on the size tag in their favorite store-bought dress or t-shirt. Retail ready-to-wear utilizes vanity sizing that varies wildly between brands and decades. In sewing, pattern size numbers are arbitrary drafting codes; only your physical tape measurements in centimeters and inches matter.

Stand in front of a mirror wearing the underwear or bra you intend to wear with the finished garment. Keep your posture relaxed with arms resting naturally at your sides. • High Bust: Place the tape directly under your armpits, straight across your upper back and above your breasts across the upper chest. Keep the tape parallel to the floor. • Full Bust: Measure around the fullest projection of your bust (across the apex/nipples) and straight across the shoulder blades in back. Do not pull the tape tight. • Natural Waist: Tie a piece of narrow elastic around your torso and bend side to side; the elastic will settle naturally into your narrowest anatomical crease. Measure at that exact line. • Full Hip: Measure around the widest circumference of your hips and buttocks, typically 18–22 cm (7–9 inches) below your natural waistline.

Most sewing patterns are drafted on a standard B-cup sloper, meaning they assume a 5 cm (2 inch) difference between the high bust and full bust. If you are a C-cup, D-cup, or above, choosing a pattern based purely on your full bust will result in shoulders that are too wide, drooping necklines, and gaping armholes. By selecting your pattern size based on your HIGH BUST measurement, the garment will fit your skeletal frame (neck, shoulders, and upper chest) perfectly. You can then adjust the full bust area through a simple Full Bust Adjustment (FBA) or by taking advantage of the pattern's built-in positive ease.

When reviewing pattern measurement tables, distinguish between: • Wearing Ease: The physiological minimum room required to breathe, sit, bend your elbows, and move comfortably. For stable woven tops, minimum wearing ease is approximately 5–6 cm (2–2.5 inches) at the bust and 4–5 cm at the hips. • Design Ease: The additional volume added intentionally by the patternmaker for style, silhouette, and aesthetic effect (e.g. an oversized boyfriend shirt or an architectural boxy top with +16 cm ease). Always compare your body measurements against both the 'Body Measurement Chart' and the 'Finished Garment Measurement Chart' to understand how loose or fitted the finished garment will feel.

Few human bodies match a single column on a standardized size chart. If your bust measures as a Size M, your waist as a Size L, and your hips as a Size XL, you do not need to choose just one size! You can blend between them on the printed pattern pieces: 1. Mark your bust size at the underarm, waist size at the natural waist notch, and hip size along the lower hip curve. 2. Using a curved ruler (such as a French curve or styling design curve), draw a smooth, gradual transition line connecting the dots. 3. Ensure the blend is smooth without sharp angles or abrupt corners that would create points when stitched. 4. Remember to blend the Front and Back bodice pieces identically so side seams remain equal in length.