How many chains do I need for a blanket? There is no one size fits all blankets answer to this question. The answer will depend on your yarn, your hook size, your gauge, your stitches, and most importantly- the desired size of your blanket.
Blankets come in multiple sizes. Blanket sizes commonly referenced in crochet patterns range from 10” x 10” lovey baby blankets to 108” x 100” king-sized blankets. See below for a chart listing all blanket sizes.
Once you know what size of blanket you want to make, you have two ways to determine how many chains you will need for your blanket.
Method 1: Chain and Measure
I recommend this method if you are using simple stitches such as single crochet, double crochet, etc. In some more complex stitch patterns, the size of the blanket will change after the chain. In these cases, its best to make a gauge swatch.
Make a chain that measures the same width as the desired width of your finished blanket. Remember to add extra chains for turning into the first row.
For example, if you want to make a blanket 60” wide and the first stitch on row 1 is a single crochet, make a 60” chain and then add 1 extra stitch for the turning chain.
Method 2: Make a Gauge Swatch
I recommend this method if you are using a more intricate stitch or pattern for your blanket such as lacing, cables, popcorn stitch, shell stitch, etc. In these stitches it can be hard to see how large the blanket will be by the chain alone.
Work up a gauge swatch using your yarn, hook, and crochet stitch or pattern that will be used in the blanket. Your gauge swatch should be a bit larger than 4” x 4”. Take a tape measure, and measure inside your swatch a 4”x 4” square. Count how many stitches are within the 4” square. This number is x.
Divide x by 4. The resulting number, which we will call y, is equal to the number of stitches required to make 1 inch of stitches.
Take y, and multiply it by the size you would like your blanket to be. This number is how many chains you need to crochet your blanket minus the turning chain. Add chains for turning. For example, if your first stitch on row 1 is a single crochet, add 1 chain. If its a double crochet, add 2 chains.
For example, Rachel wants to crochet a 50” wide blanket using a double crochet. She makes a 5” swatch that is 18 stitches wide, and there are 12 stitches within the 4” square. In this instance, x=12.
y= 3 because 12 divided by 4= 3
The amount of chains she needs for her blanket is 152, because 3 x 50 = 150 and there will be a 2 chain turning chain for the first row.
To recap,
x= the amount of stitches within the 4” measured square of your gauge swatch
y= x divided by 4
y multiplied by the desired size of your blanket in inches + turning chain= The amount of chains needed for turning