Gauge Swatch
A small knitted sample used to measure your gauge before starting a project. Essential for ensuring the correct size of your finished garment.
Explanation
A gauge swatch is a small piece of knitting you make to check your gauge. You usually knit a square of about 5-6 in (12-15 cm) in both height and width, wash and block it, and then measure how many stitches and rows you get per 4 in (10 cm). This is the most important step to ensure the finished garment is the correct size. Many skip this step, but it can result in a sweater that is way too large or too small.
Also known as: Swatch, Tension square
Knitting a swatch you can trust
Cast on enough stitches for at least 6 inches (15 cm) of width in the pattern stitch, and more is better. Work a few rows of garter stitch at the bottom and a couple of selvedge stitches at each side if the fabric curls — stockinette always does, and a flat swatch is far easier to measure accurately.
Work until the swatch is at least 6 inches tall, bind off loosely, and let it rest. Then wash and block it exactly the way you intend to treat the garment.
The swatch tells you more than a number
Beyond gauge, it shows you how the fabric behaves: whether it comes out stiff or drapey, whether the dye bleeds, how much it grows when wet, and whether you actually like the look. A fabric you dislike in a swatch is a fabric you will dislike in a sweater.
It is also the place to practice. If the design uses cables or stranded colorwork you have not done before, the swatch costs you nothing to experiment on.
How big does the swatch actually need to be?
The usual advice is a 4 x 4 in (10 x 10 cm) square, and it is the reason so many swatches lie. The edge stitches of any knitted piece are looser and more irregular than the ones in the middle, so on a swatch that size, distorted stitches are most of what you are measuring.
Cast on enough for about 6 in (15 cm) of width and work about 6 in of height. That gives you a margin of three or four stitches from each side edge and several rows clear of the cast-on, so the ruler sits entirely on fabric that behaves like the garment will. Measure in two or three places and average them — handknitting is never perfectly uniform, and a single reading is easily half a stitch out.
Common mistakes
- Binding off tightly, which pulls the top of the swatch in and skews the measurement.
- Measuring out toward the edges instead of across the center.
- Ripping out the swatch and using the yarn before the garment is finished, leaving no reserve for repairs.
Keywords
- gauge swatch
- tension square
- swatch
Frequently asked questions
How big does a swatch need to be?
At least 6 inches (15 cm) square after blocking. That lets you measure 4 inches across the middle without the edges affecting the count.
Can I use my swatches for anything afterwards?
Yes. Many knitters seam them into blankets or potholders, or keep them as a record of how a yarn behaves in the wash.
My swatch matches but my garment doesn't. What happened?
Nearly always one of three things: the swatch was worked flat and the garment in the round (or the reverse), the swatch was measured before blocking, or the swatch was measured while being held or stretched. All three produce a number that is real but describes a different fabric than the one you are knitting.