In this guide, we’ll walk through everything you need to know about sizing patterns for a perfect fit every time, from taking accurate measurements to resizing patterns for your unique body shape.
Taking Essential Body Measurements
Taking accurate measurements is the foundation of successful pattern sizing. Unlike buying ready-to-wear clothing where you might guess your size, sewing requires precision to achieve that perfect fit.
Required measuring tools
For accurate body measurements, you’ll need just a few basic items. First, a flexible measuring tape that’s soft and no wider than 1 cm is essential—metal construction tapes won’t work for body measurements. Additionally, gather a pen and paper to record your numbers, and position yourself in front of a full-length mirror. While having someone help is beneficial, you can take most measurements yourself with proper mirror positioning. For marking reference points, a narrow elastic band or string can be incredibly helpful.
Step-by-step measuring process
Before beginning, wear minimal clothing—ideally just undergarments or close-fitting clothes. When measuring:
- Stand in a neutral position with back straight, shoulders relaxed, chin up, and arms hanging naturally at your sides
- For circumference measurements, keep the tape parallel to the floor
- Hold the measuring tape snug against your body, but not too tight
- Start with your waist as a reference point for other measurements
- For women, wear a well-fitting, unpadded bra when measuring your bust
Recording your measurements effectively
Most patterns require three fundamental measurements: bust, waist, and hip. However, recording additional measurements provides better fitting options. Create a measurement reference chart where you can note:
- Bust: Measure around the fullest part, often at nipple level
- Waist: Measure the smallest part of your torso, typically above your belly button
- Hips: Measure the widest part around your bottom
- Shoulder width: From neck meeting point to shoulder edge
- Arm length: From shoulder bone to wrist
How to measure for specific garment types
Different garments require specific measurements beyond the basics. For tops and dresses, measure upper bust (around chest at armpit level) and bicep circumference. For pants and skirts, include inseam (from crotch to desired hem length), outseam (from waist down outside leg), and thigh measurements. Furthermore, when making fitted garments without stretch, take sitting measurements for waist and hips since your body expands when seated.
Remember that understanding your proportions through these measurements helps you choose the correct pattern size and identify where adjustments might be needed before cutting your fabric.
Decoding Pattern Size Charts
Pattern size charts often confuse even experienced sewists. Primarily, this happens because sewing pattern sizes are not standardized across companies. Forget what size you wear in ready-to-wear clothing—a size 12 in one pattern could be entirely different in another.
Understanding size ranges and categories
Pattern companies create their designs based on specific “blocks” (standard templates) that they then grade up and down to create size ranges. Many patterns include designations like “Misses,” “Women’s,” or “Plus Size” with each category using different proportions. Most Misses patterns are designed for a B cup with a 2-2.5″ difference between bust and high bust measurement, while Women’s patterns often accommodate a C cup with different proportions.
Finding your size when measurements span multiple sizes
Most sewists discover their measurements fall across different sizes—this is completely normal. For a fitted dress, select size based on your high bust measurement if you’re using patterns designed for B cups. For skirts and pants, the hip measurement typically determines your size. When your measurements span sizes, you can “grade” between them by:
- Drawing smooth transition lines between sizes on pattern pieces
- Checking that intersecting pieces (waistbands, facings) align properly
- Adding equal amounts to both front and back pieces when adjusting
Comparing your measurements to finished garment dimensions
Pattern companies include two critical measurements:
- Body measurements the pattern is designed to fit
- Finished garment measurements
The difference between these numbers represents ease. There are two types:
- Fitting ease: necessary for movement (breathing, sitting)
- Style ease: creates the design’s intended look
To determine if a size feels comfortable, wrap your measuring tape around your body at the finished measurement to simulate the garment.
When to ignore the suggested size
Ignore the size chart and select based on finished measurements when:
- Making looser-fitting garments with significant positive ease
- Working with stretch fabrics (negative ease might be appropriate)
- The pattern has excessive ease built in (common with major pattern companies)
- Your cup size differs significantly from what the pattern was designed for
Remember, pattern sizing is just a starting point—few patterns fit perfectly without adjustments.
Resizing Patterns for Perfect Fit
Rarely does anyone fit perfectly into a standard pattern size. After taking measurements and analyzing pattern charts, I’ve found that resizing patterns is often the crucial next step for achieving that perfect fit.
The slash and spread method for sizing up
The slash and spread method is the most reliable technique for enlarging patterns. To size up a bodice, I start by tracing the original onto sturdy paper, then make strategic cuts. For proper proportion, I cut through the center of the underarm, shoulder, and neckline/bust. When adding width, it’s important to distribute it correctly—adding nothing to the shoulder split for sizes 12 to 14, but instead adding 1/4″ to both the bust split and underarm split. Most women need more room in the bust area, not the shoulders.
Techniques for sizing down patterns
When sizing down, I use the same fundamental approach but in reverse. Instead of spreading the pattern pieces apart, I overlap them. For a bodice decreased by 1/4″, I place the bottom piece securely, then overlap the side pieces by 1/8″ on each side. The key is maintaining the pattern’s proportions while reducing its overall size. For children’s patterns, I need to slash both vertically and horizontally since adult armholes would be far too large.
Grading between sizes for proportional fit
Almost no one falls perfectly into one size category. When my measurements span different sizes—perhaps a size 10 waist with size 14 hips—I grade between them. I draw a smooth line between the notches at different points, ensuring the same changes appear on all pieces. This works effectively for up to three sizes difference; beyond that requires careful curve management and a test garment.
Digital tools for pattern resizing
Digital pattern manipulation offers precision advantages. PDF patterns can be resized during printing using Adobe Reader’s “Custom Scale” option. For more complex adjustments, specialized software like Pattern Maker or Wild Ginger provides professional-grade tools. When using projector sewing technology, I can digitally add or subtract height by moving pattern images up/down or left/right. These digital methods eliminate the need for physical cutting and taping, though seam allowances will scale proportionally with the pattern.
Remember that when resizing patterns, ease must be maintained. A pattern needs room for movement, and correct proportions ensure the final garment both fits and flatters.
Common Sizing Problems and Solutions
Even after taking precise measurements and selecting the right pattern size, fitting issues can still arise. Many sewists struggle with fitting at one time or another, primarily because our bodies have unique proportions that don’t match standardized patterns.
The first step in resolving fitting problems is making a muslin (test garment) using fabric similar in weight and drape to your final fabric. This crucial step reveals potential issues before cutting into your good fabric. When trying on your muslin, look for signs of poor fit: undesired tightness, excess fabric, drag lines, inadequate length, uneven hem, or gaping.
When addressing multiple fitting issues, work systematically from the shoulders down. This approach makes sense because adjustments made to upper areas often affect how lower sections fit. Consequently, fixing shoulder issues first might eliminate the need for additional changes elsewhere.
Among the most common fitting problems:
- Gaping necklines can be fixed by slashing from neckline through bust area to waist and overlapping at the neck edge
- Full or small bust issues require specialized adjustments to add or remove fabric appropriately
- Waistline fit problems are best corrected by dividing adjustments between darts and side seams
- Full thigh adjustments need extension of the back crotch at inner thigh
- Sleeve cap issues often require redistributing fabric or adjusting the armscye
Despite the temptation to fix every minor issue, resist over-fitting. Remember that clothes aren’t meant to fit like a second skin—a perfect fit while standing might restrict movement throughout your day.
Fabric choice also makes a significant difference in fit. A pattern that fits perfectly in muslin might need additional ease in thicker fabrics—sometimes requiring up to 1.5 inches more room! Accordingly, when working with heavier fabrics, consider adding extra seam allowance for adjustment flexibility.
For persistent fitting challenges, consider your “fitting landscape”—not just your measurements but your body shape and proportions. Taking reference photos along with measurements can provide visual insights that numbers alone cannot capture.
Conclusion
Learning how to size sewing patterns correctly transforms your sewing journey from frustrating to fulfilling. Throughout this guide, we’ve explored the essential elements of achieving that perfect fit for your handmade garments.
Taking accurate measurements serves as the foundation of successful pattern sizing. Your body’s unique proportions rarely match standard pattern sizes exactly, which explains why most sewists find their measurements spanning multiple sizes. This reality, though initially confusing, simply reflects our wonderfully diverse body shapes.
Pattern size charts often bewilder even experienced sewists due to their lack of standardization across companies. Remember, your ready-to-wear clothing size means little when selecting pattern sizes. Instead, focus on finished garment measurements and ease allowances for truly comfortable, well-fitting clothes.