Knit to Flatteris all about steering you through the process of creating sweaters you love to wear. I recommend starting by choosing a size to fit your shoulders, and then modifying the rest of the sweater.

There are several reasons for this, all aimed at making life easier for the knitter:

  • If the sweater doesn’t fit in the shoulders, it looks ill-fitting. Period.
  • Sleeve cap math (or math for the shoulders generally) is the hardest to modify of all the maths you might change up.
  • Modifications to the front of the sweater (or the back of the sweater) don’t necessarily have to affect any other piece–often, you can knit 3 out of 4 pieces as written in the pattern or with minor changes like length. Then, tackle the last piece once you’re comfortable with everything else.
  • Wouldn’t most of us rather divide once than deal with the Pythagorean Theorem several times?

For most knitters, choosing a sweater size based on your upper torso (the total circumference of your torso above the bust, instead of at the fullest point) is the only thing required to get a great fit in the shoulders. But of course, like everything else considered across all of humanity, there are exceptions.

Jackie (who you’ll be seeing a lot of around here since she’s now helping me run AHD behind the scenes) just so happens to be one of those outliers: Her shoulders are broad, and her torso is much smaller. Choosing a size based on her upper torso instead of her bust results in a much better fit than she’d gotten before…

…but hanging around me rubs off, apparently, because “a much better fit” doesn’t seem so great once you’ve seen perfect. You know? Case in point: Minx.


Overall this tank is great on Jackie–she modeled it when I was sending snapshots to my editor–but the cross-chest (width of the sweater after all armhole decreases are complete) is juuuust a bit too narrow. The picture above shows the way the tank looks after an hour or so of wearing it.

In Jackie’s case, sweaters that fit her upper torso, bicep, and bust result in a cross-chest that’s just a little too narrow. Reworking the armhole decreases (literally, just doing fewer of them) result in a much nicer fit. Here’s Jackie’s own Minx:


See how the armholes are just ever so slightly more where they should be? Perfection. (Photo credit Caro Sheridan.) Though Jackie has reported no problems in the sweaters she’s altered in this way, doing so is slightly risky. Here’s a short list of all of the changes to a sweater that will affect the sleeve cap calculations:

  • Bicep changes
  • Cross-chest changes (e.g. by altering the number of armhole decreases)
  • Armhole depth changes
  • Major row gauge changes vs. the pattern’s

Essentially, when you change one of these sweater elements you’re changing the length of either the armhole side or the sleeve cap side of where some complicated connecting needs to happen.

I’ll be doing a fuller post on sleeve cap mods (and their ins and outs) soon, but in the short run: What do I recommend as a short cut to perfect sweaters for those knitters who require these mods? Well, I think your best bet is to use this fabulous armscye calculator. Here’s how it can be used: Put in all of the information as written in the pattern except what you’re changing, where you should put the new info. (For example, if you’re enlarging the bicep, put in everything as written except the max stitch count. Substitute your own stitch count there.) The calculator will give you a number of decreases over a number of rows in the “curved” portion of the sleeve cap.

You can then either fudge it, draw it out on knitter’s graph paper, or some combination of the two, to figure out how often to decrease when you’re knitting the cap.

Is it as easy as recalculating waist shaping? No… but it’s not that much harder, either. And isn’t sweater perfection worth it?