In previous posts, I have discussed how to use Elizabeth Zimmerman’s Percentage System (EPS) to design and knit a sweater and how to modify a written pattern to adjust for changes in sizing and/or gauge. Today, I will briefly describe the process of designing a sweater without a written pattern. I learned this process in depth when I first knitted a sweater using my knitting machine. Knitting garments on a knitting machine requires extensive set-up and calculations before you can even begin to knit. Regardless of whether you are hand knitting or machine knitting – the process and calculations are the same.

As in the previous design techniques, you start with a good set of body measurements and a gauge swatch to determine your stitch and row gauge. You will also need to factor in the amount of ease you wish to have in your completed sweater.

Any sweater has several basic elements: The front & back, the sleeves and the neck. Sweaters come in two basic forms – the pullover and the cardigan. If you take a minute to think through all the sweaters you have seen, you will realize that all of them are some variation of these two basic forms. So, let’s start by breaking down the elements of a basic pullover sweater.

Elements of a Pullover Sweater:

• The Front & Back – in a very basic design, the front and the back are the same up to the point where one shapes the neckline. The Front and Back make up the tube of fabric that goes around the entire body – thus, the back consists of one-half of the total number of stitches needed for the body/chest measurement and the front has the other half. In our basic design, the back/front is essentially a rectangle – and you need to determine the width and the length from your own measurements. If you plan to knit this sweater in the round, then you will calculate the total number of stitches based upon the body/chest measurement plus ease. [(BM + Ease) X SPI]. If you plan to knit this sweater in pieces and then sew the pieces together, you will calculate the number of stitches needed for the front/back by dividing the Body/chest measurement by two and then adding in Ease and multiplying by your stitch gauge. [((BM/2) + Ease) X SPI]. For a set-in sleeve, you will also need to calculate the shaping of the armhole. When knitting in the round, at the point you begin shaping the armholes, it is best to knit flat and knit the front and back separately.
• The Neck – the most basic neck for a pullover sweater is a round or crew neck shape. In our basic sweater design – a portion of the stitches of the center back are used for the back of the neck, while in the front there is some shaping done to make the front of the neck slightly lower than the back. The stitches not used in the neck are used for the shoulders and form the shoulder seams of the sweater. It is best to use live stitches for necklines. This allows you the needed stretch for the fabric to go over the head of the wearer. One must also keep in mind that the average woman’s head has a circumference of 22 inches. Thus, there needs to sufficient width allocated to the neck to allow the head to pass through it.Back Neck – for the basic sweater pattern, the back does not have any shaping to it. It is simply divided into three sections: Left shoulder, Neck and right shoulder. The number of stitches assigned to the back neck stitches is somewhat proportional to the chest measurement. Generally, the wider the chest, the larger the neck circumference. In this basic sweater design, there should be an equal number of stitches allocated to the shoulders, with the remaining stitches placed on hold for the neck. You determine the number of back neck stitches by multiplying your stitch gauge by the width of the back neck. You then subtract the number of back stitches from the total number of stitches for the back at the shoulders – this will give you the number of stitches for the shoulders. This number needs to be divisible by 2, so you may need to take 1 stitch from your neck stitches to even it out.

  Front Neck – the shaping for the front neck begins below the last row of the shoulder. For women, the depth of the neckline starts 2.5 to 3 inches below the shoulder, for men, the depth is 3 inches to 3.5 inches and for children the depth is 1.5 to 2.5 inches. This depth is entirely a matter of preference. The front neck is shaped as a semi-circle by gradually eliminating stitches on either side of the center front neck stitches. Thus, the center front stitches are placed on hold and then decreases are done on either side of these stitches as you knit up to the shoulders. This shaping will occur concurrently with the armhole shaping

• The Sleeves – the most common styles of sleeve in commercial sweaters are the drop-sleeve and the set-in sleeve. For this design, I will cover the set-in sleeve. A Set-in Sleeve joins the body of the sweater at the armhole and the top of the shoulder seam. Set-in sleeves require shaping at the top of the sleeve itself as well as corresponding shaping in the front and back. The shaping is made by a series of bind-offs, increases and/or decreases. To design your sleeve you must have your sleeve length, the width of the sleeve at the armhole, the width of the sleeve at the elbow and the width of the sleeve at the wrist. You also need the depth of the armhole. There are quite a few calculations required to be able to knit a properly fitting set-in sleeve. You begin by calculating the shaping of the sleeve from the wrist to the underarm and then calculate the shaping required to form the rounded sleeve cap. Shaping is achieved by a series of increases from the wrist to the underarm, followed by bind-offs and decreases to form the sleeve cap.

Now let’s look at a basic cardigan sweater.

Cardigans are most often knitted flat – either in separate pieces or in as a one wide piece on a long circular needle. They can be knitted in the round using a steek to separate the two fronts when finishing the sweater. Shaping for armholes and neckline are mirrored for the right and left fronts. In addition, there is a knitted band of fabric that overlaps at the center front – this band can be knitted concurrently with the front using a pattern stitch or can be added to the front by picking up stitches along the center front edge after the front has been knitted.

The calculations for this sweater are essentially the same as for our basic pullover – with the exception of the front. A cardigan sweater has two front pieces that meet and overlap in the center of the garment. This means that each front piece is one-half of the front piece of a pullover sweater, plus some added width for the overlapping parts(buttonbands or borders). In our basic sweater design, you simply add the desired width of the buttonband to each front piece. For example, the front on our pullover measures 40 inches. For our cardigan, each front piece would be half of that or 20 inches and the buttonband would be 2 inches wide: 20 + 2 = 22 inches. My Excel Spreadsheet includes a section on calculating the fronts for a cardigan.

I have created an Excel Spreadsheet for all the calculations required for a basic pullover with a set-in sleeve. Click here to download the spreadsheet: Sweater Calculator.

Using this calculator and your own gauge, you now have all the calculations required to knit your pullover sweater. You can knit this sweater from the top down or from the bottom up. The shaping for a top-down sweater is done in the reverse order of a bottom-down sweater.

Terms of Use: You may electronically copy and print to hard copy portions of the spreadsheet for the sole purpose of using materials it contains for informational and non-commercial, personal use only. Any other use of this spreadsheet — including any commercial use, reproduction for purposes other than described above, modification, distribution, republication, display, or performance — without the prior written permission of Lindy’s Knits & Laces is strictly prohibited.

Today I have briefly outlined the basics of designing your own sweater using two basic sweater designs. From these two basic designs, you can create a sweater according to your own measurements out of any weight yarn. I recommend you give it a try. Listed below are some references for your further exploration – I have only scratched the surface of this topic. Happy Knitting.

If you find this post and/or my spreadsheet helpful , please leave me a comment. Thanks!

For further exploration – check out these sources:

Maggie Righetti, Sweater Design in Plain English
Leslye Solomon, The Uncomplicated Knitting Machine
Deborah Newton, Designing Knitwear.
Barbara G. Walker,Knitting from the Top Down.
Vogue Knitting