Gauge & Cast On Calculator

Knit & crochet

Enter your swatch gauge and the size you want. Get the cast on or chain, the rows, and how wide a pattern comes out at your gauge.

Quick answer. At 18 stitches and 24 rows per 4 in, a 20 x 60 in piece needs a cast on of 90 stitches and about 360 rows.

Source: stitches per inch (gauge / 4) times width, rows per inch times length.

Your gauge

1. Swatch

sts
rows

Measure across the middle of a washed, blocked swatch, away from the edges.

2. Size you want

in
in

3. Pattern repeat (optional)

sts
sts

For a pattern worked over a multiple of 4 plus 2, enter 4 and 2. Leave 1 and 0 for plain fabric.

4. Check a pattern (optional)

sts

See how wide a pattern comes out at your gauge instead of the pattern's.

Result

0

Your numbers

Crochet: add the turning chain to the starting chain (1 for sc, 2 for hdc, 3 for dc).

The gauge formula

  • Stitches per inch = stitches per 4 in / 4
  • Cast on = width x stitches per inch, rounded to your repeat
  • Rows = length x rows per inch
  • Width of a pattern at your gauge = pattern stitches / your stitches per inch

Cast on for a 50 in blanket by yarn weight

Using the middle of the Craft Yarn Council's stockinette gauge range for each weight. Your own gauge will differ.

Cast on for a 50 inch wide knitted blanket
Yarn weightGauge range per 4 inMid gaugeCast on
1 Super Fine27 to 32 sts29.5369
2 Fine23 to 26 sts24.5306
3 Light21 to 24 sts22.5281
4 Medium16 to 20 sts18225
5 Bulky12 to 15 sts13.5169
6 Super Bulky7 to 11 sts9113

50 in is 127 cm. Gauge ranges from the Craft Yarn Council Standard Yarn Weight System.

How to measure gauge

  1. Work a swatch at least 6 in (15 cm) square in the stitch the pattern uses.
  2. Wash and dry it flat, the way the finished piece will be treated.
  3. Lay a ruler across the middle and count the stitches in 4 in, halves included.
  4. Count rows over 4 in the same way, vertically.

More stitches than the pattern means your fabric is tighter, so go up a needle or hook size. Fewer means go down.

Sources

Common questions

How do I calculate how many stitches to cast on?
Divide your stitches per 4 in by 4 to get stitches per inch, then multiply by the width. At 18 stitches per 4 in, a 20 in piece is 90 stitches.
How many stitches do I cast on for a scarf?
At a bulky 14 stitches per 4 in, an 8 in scarf is 28 stitches, and 280 rows at 16 rows per 4 in makes it 70 in long.
What if my gauge does not match the pattern?
Your piece changes size. A pattern that casts on 90 stitches at 18 per 4 in is 20 in wide, but at 20 per 4 in it comes out 18 in. Change hook or needle size, or let this calculator redo the counts.
How do I round to a pattern repeat?
Enter the repeat as a multiple plus extra. For 2x2 rib (multiple of 4 plus 2) 21 in wide at 22 stitches per 4 in, cast on 114.
Is gauge over 4 inches the same as over 10 cm?
Close enough. 10 cm is 3.94 in, a 1.6% difference that is smaller than normal swatch variation, and patterns treat them as equal.
How big should a gauge swatch be?
At least 6 in (15 cm) square, so you can measure 4 in across the middle away from the edges. Wash and dry it the way you will treat the finished piece.