Happy Monday, dear T.H.R.I.V.E. Association family! One question that our staff frequently get asked is how many stitches would need to be cast on for a scarf (garter, rib, etc.) that would meet T.H.R.I.V.E. Association’s scarf dimension requirements (6 in. x 60 in. [15 cm. x 152 cm.]) Unfortunately there is no hard number, as something like this is heavily reliant on the individual crafter’s tension, their chosen knitting needles/crochet hook size, and the chosen pattern.
The most important part of the success of any handcrafted garment is the individual crafter. You might choose a pattern for a garment that you are absolutely in love with, put in the hours of hard work, use the same yarn and the same size needles/crochet hooks, etc. that the pattern calls for, but still end up not having a garment that is the correct size or feel (i.e. the weave is too loose, or it is so tight that it stands up on it’s own). This is largely due to variations in crafter tension and a failure to account for those variations in your project. The pattern is going to be the same for each crafter that uses it, but the results won’t necessarily be the same unless you know your tension BEFORE you start and account for that difference. The only way to do this is to make a gauge swatch using the same tools/materials/etc. that you will be using for your chosen handcrafted garment. That swatch is your guide to figure out whether or not you are knitting/crocheting to gauge or if you need to change your crafting tool size to obtain the requisite gauge.
So, to return to the original question of how many stitches are needed for a 6 in. x 60 in. (15 cm. x 152 cm.) scarf, let’s approach this bit by bit. Choose your yarn and look at the label. Most modern yarn labels have a recommended gauge using a certain needle/hook size and number of stitches. In the photo above, the Red Heart Camouflage yarn suggests that knitting a stockinette swatch that is 17 stitches across for 25 rows when using a Size 8 US needle results in a 4 in. x 4 in. swatch. Once you have made a stockinette swatch using those numbers with this yarn, you can now adjust as needed. If your swatch measures smaller than the recommendation, then go up a needle size. If your swatch is larger, go down a needle size. The same is true when crocheting.
In summation, there is no hard and fast answer to this question. There are multiple variables to take into account. In the case of using the yarn and stockinette swatch from our example, to find how many stitches are required for a width of 6 inches (which is the minimum width requirement for all scarves donated to T.H.R.I.V.E. Association), we would divide 17 by 4 to find out how many stitches are in each inch. Once we have that answer, we would then multiply that number by 6. In other words:
17 / 4 = 4.25
4.25 x 6 = 25.5
Thus, if you were knitting a stockinette scarf you would cast on about 25-26 stitches with size 8 US needles if your stockinette swatch was knit true to gauge. It is important to emphasize that the main variable is the crafter.
Note: Another variable that needs to be considered is the stitch that you choose to use for the scarf that you want to donate. For example, a rib scarf will need more stitches to be cast on as it will stretch. This is why a gauge swatch using your chosen materials, needle size/crochet hook size, and pattern will ultimately lead you to getting the best results.