All about Spreadsheet Patterns
Confession - I've put off writing this for 18 months. It feels really high stakes, and it's a topic that requires nuance. I'm writing my thoughts here, but I hope you'll take some time to listen to the KnitFix and Chill episode Bess & I released that covers this in more detail.

Are spreadsheet patterns better?
Any online talk about size inclusion eventually results in someone mentioning formula patterns. Whether they’re generated with software or they include an excel workshop, these are patterns that promise a custom-fit sweater based on your measurements.
And I’m talking about generating the WHOLE pattern. Some patterns include modifications you can make and they might reference formulas to help you get a custom fit bicep or bust adjustment. But formula patterns generate the whole pattern based on your measurements.
Sounds dreamy, right? So why doesn’t everyone do them?
In my opinion (and this is an opinion piece, and I’ll be sharing the basis for my opinions), formula patterns are great for some projects and knitters and not so great for others. Let’s dig into it!

First - my lens
I am, as you know, deeply excited by the pursuit of great fit. And I define that as a garment that doesn’t tug, ride up, hang unevenly, bunch, etc. – within the constraints of the construction (loose fitting garments will always have some extra material in the underarms, for example). So this conversation, in my spaces, is always going to be centered around the following question.
What is the most efficient and pleasant way for a knitter to achieve a great fit?
Every knitter will benefit from making at least one fit modification. I have yet to meet a single human being who matches 100% of my size chart’s 29 measurements. In sewing, we expect to make modifications – it’s just a matter of how many. We make a whole mock-up (a muslin) of the thing we’re going to spend our time and money on. In knitting, we often choose a size based on full bust and cross our fingers. Even if you’re working from a formula pattern, there are assumptions that underlie the pattern and you should still expect to make a modification.
So for me, answering the question “are formula patterns good” starts with answering the question “how much work is the knitter going to have to do, and what is their desired outcome?”
The limits of formula patterns
Garment complexity. These patterns don’t tend to handle complexity as well as a standard pattern. For example, I put shaping in all of my necklines (decreases you work in the ribbing) so that the neckline lies flat without rippling. That is something you’re unlikely to see in a pattern where the neckline is variable.
They are subject to the fit and grading skills of the designer. Just like any other pattern, there are grading decisions that shape the final outcome. If the designer doesn’t know that a sweater needs front neck shaping, the formula pattern will still fit poorly.
They compromise finesse. In a standard pattern, the designer will review all the rounding decisions the spreadsheet makes, and override them to create a more beautiful finished product. I often plot the curve of the underarm, for example, and draft the shaping based on the desired curve rather than relying on the standard underarm shaping formulas.
They rely on the knitter taking excellent measurements. Not all knitters have a second person handy, and even experienced knitters may not know exactly how to measure their armscye, for example. This measurement in particular is so critical to fit, and not having it entered accurately can render a pattern unwearable. While I find this measurement to be highly variable and to be a stress point even in standard patterns, knitters can at least know that they’ll be starting off with something in the ball park of accurate.
They over-promise. The promise of a ‘custom fit’ pattern can trick the knitter. Believing that you’re getting something that is totally customized to every single one of your measurements can lead less sophisticated knitters into trouble. They may not know that they should still review the schematic. I pulled one pattern, for example, that drafted a set-in sleeve for me without asking for my cross front. It totally relied on my full bust and assumed a shoulder measurement for me. I had to manually remove 4” of width from the shoulders. If I were less experienced in fit, that would have been a very sad experience for me.

The benefits of working with formula patterns
For knitters who have to make many large adjustments to standard patterns, formula patterns can simplify the modification process substantially. Knitters who find themselves totally different sizes at the bust, hips, and shoulders often find that a spreadsheet pattern requires less finessing than a standard pattern.
Spreadsheet patterns can do a reasonably good job of drafting set-in sleeve sweaters. This is one of the most adjustable constructions, and each measurement can be adjusted separately, making them a better candidate for spreadsheet designs.
Knitters who are less interested in perfect fit and bespoke shaping and are seeking a pleasurable knit, a relatively simple design, and a reasonably well-fitted garment will probably find these types of patterns fit better than a standard design of the same type.

My checklist
As preparation for this piece, and for the podcast episode Bess and I recorded (check out KnitFix and Chill Ep 15 here!), I wanted to purchase a formula pattern I could envision myself making one day. Here are my tips based on reviewing some real patterns and talking to knitters who’ve had both spectacular and terrible formula pattern experiences:
Review the pattern and the schematic the same way you would any other pattern. Does it have front neck shaping? Underarm shaping? Shoulder shaping? If there isn’t a schematic available before you buy, see if the pattern seller will share the schematic for the one in the picture. If the sample didn’t have that shaping, you won’t either. For more tips on evaluating patterns, check out this three part article series that starts here.
Confirm that the pattern will at least have an illustrated schematic once you buy it. And not just bust, bicep, sleeve length, and body length. You’ll NEED armhole depth, front neck depth, shoulder rise, and wrist.
Skip patterns that have you input a mix of body measurements and garment measurements (for example, your actual bust and your preferred sleeve length to the underarm. Sleeve length to the underarm depends on yoke depth, and is not a suitable way to construct a sweater.)
Skip patterns that suggest you contact the designer if you get a negative number. You shouldn’t encounter a negative number.
Skip patterns that don’t recommend a specific yarn weight and fiber. Yarn properties have a big impact on grading. If the pattern’s underlying formulas don’t factor in how the properties of the yarn will impact different sizes, that’s a grading red flag. For example, the heavier sleeves are, the more they pull a neckline to the side, making it wider and shallower. Good grading will factor that in, and heavier yarns will have necklines that apply slightly narrower and deeper grade rules as sweater sizes get larger. If you swap out a light, lofty yarn with lots of grip instead? The neckline will not look as pictured.
TL;DR
If you’re curious about these patterns, you should totally experiment with one! After all, $12-15 is a reasonably low-risk way to see if you’re into something. Put your measurements in, see what the schematic yields, and if you like it? Knit away!
If you’d like to hear a more lengthy discussion on this topic, Bess and I dig into it on YouTube, here. We hope this episode helps you understand these patterns better, and get a better sense of whether they are right for you and how to use them!
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