Planning a squares blanket properly
A granny square blanket is the most forgiving big project there is — small, portable pieces, no long rows, and you can stop after any square. What it isn't is easy to guess at. Make forty squares and then discover they're 5½ inches rather than 6, and your blanket is four inches narrower than planned, with a border that no longer balances.
So make one square first, block it if you intend to block the finished blanket, and measure it honestly. Everything else follows from that number.
Squares are rarely the size the pattern says. A "6 inch granny square" made by six different people will come out anywhere from 5 to 7 inches, depending on hook, yarn and tension. This isn't a mistake on anyone's part — it's simply gauge. Measure your own and plan from that.
Choosing a square size
Smaller squares — 3 or 4 inches — give a lovely detailed patchwork and use up scraps beautifully, but there are a great many of them and a great deal of joining. Larger squares of 8 or 12 inches grow fast and suit bold, simple designs. Six inches is the popular middle ground for good reason: a throw takes around 50 squares, which feels achievable without being fiddly.
Don't forget the joining
How you join affects the finished size more than people expect. Whip stitching squares edge to edge adds nothing, while a decorative crochet join can add half an inch or more between every pair of squares — across ten squares, that's five extra inches of width. The calculator accounts for your chosen method.
Ends, and how to suffer fewer of them
Fifty squares in three colours can mean three hundred ends to weave in, which is the reason many blankets stall in a bag. Two habits help enormously: crochet over your ends as you work the next round, and weave in the ends of each square as you finish it rather than saving them all for the end. A pile of finished squares is a joy; a pile of unfinished ones with tails is a chore waiting.
Making time
The estimate above assumes roughly twenty minutes for a six-inch double crochet square once you're in the rhythm, plus joining and border time. Take it as a guide rather than a promise — a plain square goes faster, a fancy one much slower, and everyone's pace differs. What it's useful for is knowing whether a blanket is a two-week project or a two-month one before you commit.
Questions we're often asked
How many granny squares do I need for a blanket?
It depends on square size and blanket size. A 50 × 65 inch throw made from 6 inch squares needs around 70 squares once joining is allowed for; from 4 inch squares, closer to 160. Enter your own measurements above for an exact figure.
What size should a baby blanket be?
Around 30 × 35 inches is the usual size for a baby blanket, and 14 × 16 inches for a pram or car seat cover. Cot blankets are larger at about 36 × 52 inches.
How much yarn does a granny square blanket use?
A DK throw of about 50 × 65 inches typically takes 1,800 to 2,200 yards including the border. Chunky yarn needs fewer yards for the same size and fingering considerably more — the calculator adjusts for the weight you pick.
How do I lay out the colours?
Make all your squares first, then lay them on a bed or floor and shuffle them until the arrangement pleases you before joining a single one. Photograph the layout with your phone, so you can put it back if the pile gets disturbed — this trick has saved a great many afternoons.
Should I block my squares?
It makes joining far easier and the finished blanket noticeably neater, especially with lacy squares that curl. Block a few at a time on a towel with rustproof pins, and measure a blocked square when planning — since that's the size it will be in the finished blanket.