Many of the patterns I write are based on a variable gauge, so knitting a proper swatch is crucial. I find that for smaller items, a 2″ swatch is sufficient, but you will need a larger swatch for larger projects (4″ is standard), or for items where the fit is extra important. I like to make swatches that have a border of garter stitch, since this helps the swatch lie flat, which makes for easier measuring. Here is how I knit a (roughly) 2″ swatch of stockinette*:
1. Cast on 2 inches plus four stitches. Using a long-tail cast on and about 18 inches of tail (I usually measure from my fingertips to elbow), cast on stitches until you have at least 2″ of stitches on the needle. Record this number of stitches as your “stockinette stitches.” Then, cast on four more stitches (these extra stitches will be the garter stitch margins.)
2. Knit 3 rows to establish the bottom garter margin.
3. Knit a stockinette square**, with garter edges: Start with a wrong side row: Knit 2 stitches, then purl until you are at the last 2 stitches – you will have purled the same number of stitches as your “stockinette stitches” number recorded earlier. Knit the last two stitches. For the right side, knit the whole row. Repeat these two rows until the stockinette portion of the swatch is square (ignoring the garter sections), ending with a knit row.
4. Knit 2 more rows to finish off with another garter margin, and then…
5. Bind off. I am stingy with my yarn and usually immediately unravel the swatch after measuring, so I do not cut the yarn after binding off. A more staunch knitter than I would cut the yarn, and then wash and block the swatch before measuring, but who has time for that? It’s probably a good idea if you are knitting an entire sweater in fingering weight that you intend to wash many times, or if you are knitting anything lace, but for baby leg warmers? Ha. Ha ha ha.
6. Measure. Then measure again. And once more for good… measure. It’s really important you do not skip this step and just assume you have exactly two inches of stockinette. Measure the full width of your stockinette section, ignoring the garter stitch margins, and record this number as your “stockinette inches.” Do not round up or down to the nearest inch. If you get 2 3/8 inches, write down 2 3/8 inches. Do this at least three times, in different places on your swatch, to make sure you get the same length each time. If one of your measurements is not like the others, ignore it. Also, be sure that you are measuring in a straight line (as opposed to ever so slightly diagonally across several rows. Ask me how I know.)
7. Compute stitches per inch. Divide your “stockinette stitches” number by your “stockinette inches” number to get “stitches per inch”. Use a calculator (or say, the search bar of google.) You probably won’t get a nice even number, and that’s ok. From here, what you do with this number depends on your pattern.
– If you are following one of my patterns that uses a variable stitches per inch, use the first two numbers after the decimal place (e.g. 9.4723 becomes 9.47). Record this number, and proceed to following the pattern.
– If you are aiming to match an existing gauge for a pattern, compare your stitches per inch to the pattern gauge. The pattern may give a gauge as a number of stitches over a number of inches. If this is the case, you need to multiply your “stitches per inch” by the number of inches listed in the pattern gauge (usually four inches). If your number of stitches per inch (or two inches, or four inches, etc.) is smaller than the pattern calls for, you will need to knit another swatch on smaller needles. If your number is bigger than the pattern calls for, you will need to knit another swatch on bigger needles.
Still confused? Let’s do some examples from my sample swatch and the measurements above:
Scenario 1: Say you want to use one of my “variable-gauge” patterns – just use 3.11 as your stitches per inch, plugging it into calculations according to the pattern.
Scenario 2: Say you are using a pattern that calls for 12 stitches over four inches. Multiply your stitches per inch times four – 3.11 x 4 = 12.44. Use your judgement – is this a pattern for something small and stretchy, like mitts? Or for something where you wouldn’t mind if the final product is a few inches off, like a drapey infinity cowl? Then you’re probably good to go. If not, you need to redo the swatch on different needles. Since your number (12.44) is bigger than the pattern number (12), try the next size up in needles. If your resulting swatch gave you a number that was too small, you would just use whichever needle size gave a result closer to 12. If it was still to big, go up in needle size again, and so on, until you find a good enough match. Does all this sound like a pain in the ass? It kind of is! Which is why I started designing patterns based on whatever gauge you want.
Notes for the adventurous: If you want a bigger swatch, just cast on more stitches, ignoring the “aim for two inches” part of step one. This method will also work for getting a gauge in a pattern other than stockinette – just replace the stockinette part with your pattern stitch. If you are also concerned with row gauge, keep track of how many rows you knit in step 3. The only steps where it is important to be precise is in recording your number of (non-margin) stitches and/or rows, and measuring when you are done. Everything else is flexible.
*Stockinette is knitted on one side (e.g. all odd rows), and purled on the other (e.g. all even rows) – or, if knitting in the round, stockinette is produced by knitting every round. Garter stitch, on the other hand, is produced by knitting every row – or alternating rounds of knit and purl, if knitting in the round.
**Or, if you are feeling like a lazy cheater/risk taker, knit a stockinette Practically-a-Square. (Two inches by one inch is basically square, right?) I do this a lot, especially when the project in question is not very gauge dependent (think stuffed toys, dishcloths, scarves).