Knitting & crochet calculator

Top-Down Raglan Yoke Calculator

Enter your gauge, desired chest size, neckline circumference, and yoke depth to generate your customized neck cast-on breakdown, step-by-step raglan increase sequence, and underarm split counts.

Knitting a top-down seamless raglan sweater offers the joy of trying on your garment as you go with zero seaming required at the end. However, calculating the increase frequency so that the chest circumference and the armhole depth finish at the exact same round is one of the trickiest parts of sweater design.

This calculator divides your neckline cast-on into proportional sections for the back, front, sleeves, and 4 raglan seam lines. It then calculates the exact number of increase rounds, interval spacing, and underarm cast-on stitches needed to hit your target chest ease perfectly.

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Frequently Asked Questions

How do I measure neckline circumference for top-down sweaters?

Measure around the base of your neck where you want the sweater collar to sit, adding 2 to 4 inches (5 to 10 cm) of ease so the collar comfortably pulls over your head without choking.

What are the 4 raglan seam lines?

Raglan seam lines run diagonally from the neck down to each underarm. Stitches are increased on both sides of each raglan line (4 lines ร— 2 increases = 8 stitches added per increase round).

Why do underarm cast-on stitches matter?

Underarm stitches are cast on beneath each armpit when dividing the body and sleeves. They provide essential three-dimensional armhole depth and ease so sleeves do not pull or bind under the arm.

What increases should I use along the raglan lines?

M1R (Make 1 Right) before the raglan seam marker and M1L (Make 1 Left) after the raglan seam marker create neat, symmetrical diagonal increase lines without leaving eyelet holes.