Sewing pattern size calculator

There is no universal sewing size chart. Every brand drafts to its own measurements, so this calculator works from the chart printed on your pattern. Type in your measurements and the pattern's body measurements, and it tells you which size to cut and where to grade between sizes. Nothing you type leaves this page.

Find your size

Units

Inches Centimeters

Your body measurements

Full bust Around the fullest part High bust Optional. Under the arms, above the bust Waist Natural waist Hip Around the fullest part

What are you sewing?

Garment Top, shirt or jacket (sized by bust) Dress or jumpsuit (sized by bust, graded to waist and hip) Skirt, trousers or shorts (sized by hip) Cup the pattern is drafted for Full bust minus high bust. Big 4 patterns use about 2 in (5 cm). Check your pattern's instructions.

Your pattern's size chart (body measurements, not finished garment)

Size	Bust	Waist	Hip

Add a size Try an example chart Clear the chart

Find my size

Check the ease

Most patterns also print finished garment measurements, on the envelope or on the tissue near the bust line. Compare one with your body at the same spot. Uses the units chosen above.

Your body at the bust Finished garment at the bust

Check the ease

Your pattern always wins. Different brands size differently, and the size chart, finished measurements and fit notes on your pattern beat any calculator, this one included. Use the result as a starting point and make a muslin when the fit matters.

How this is calculated

1. Your size for each measurement. The chart is sorted from smallest to largest, and the calculator takes the smallest size whose chart measurement is equal to or bigger than yours. If you fall between two sizes it picks the larger one, because a seam can be taken in but not let out. Below the smallest size you get the smallest size. Above the largest it says so instead of guessing.
2. Which measurement picks the size. Tops and dresses are sized by the bust, because shoulders and armholes are the hardest to alter. Skirts and trousers are sized by the hip. If another measurement lands in a different size, the result tells you where to grade.
3. High bust. Patterns are drafted for one cup size. If you enter a high bust and your full bust minus high bust is more than the cup the pattern is drafted for, the top is sized by high bust + drafted cup instead, so it fits your shoulders, and the result suggests a full bust adjustment.
4. Ease. ease = finished garment − body. For tops and dresses at the bust, a common guide (Threads magazine) reads it as: below 0 is negative ease, for stretch knits only. 0 to 3 in (7.6 cm) is close fitting. Over 3 to 4 in (10.2 cm) is fitted. Over 4 to 5 in (12.7 cm) is semi fitted. Over 5 to 8 in (20.3 cm) is loose fitting. More than that is very loose. The fit description on your pattern envelope wins over this guide.

Grading between sizes

Grading means drawing a smooth line from one size to another. If your bust is a 12 and your hip is a 14, trace the 12 line at the bust, then curve gently out to the 14 line by the hip, on the front and back pieces alike. Keep seams that join the same length, so they still match when you sew them.

Sewing your size with Sttchr

Once you know your size, Sttchr helps you trace it. In the app you pick your size once, and when the PDF has size layers only that size shows on the fabric, so you follow one clean line. See how to select a size in Sttchr, or how the sewing pattern tracer puts your pattern on the fabric at true size. Looking for something to sew? Browse patterns in the shop.

Questions

Is there one size chart for all sewing patterns?

No. Each brand drafts to its own body measurements, and a size 12 in one brand can be a 16 in another. Always use the chart printed on the pattern you are sewing.

What if I am between two sizes?

This calculator picks the larger size, because a seam can be taken in but not let out. If your measurements land in different sizes, grade between them, for example from one size at the waist to another at the hip.

What is ease in sewing?

Ease is the difference between the finished garment and your body at the same spot. Positive ease gives room to move and sets the style, from close fitting to very loose. Negative ease means the garment is smaller than you and only works in stretch fabrics.

Next step: work out how much fabric you need for your size.