Work out exactly how many squares — and rounds — your project needs.
Granny square projects are modular by nature, which makes them easy to plan — once you know the finished size of a single square, everything else is simple multiplication. This calculator works out how many squares fit across and down your target dimensions, the total square count, and if you know how much yarn one square takes, an estimate of total yarn needed too.
How many granny squares do I need for a blanket?
Divide your target blanket width by the finished size of one square (after joining) to get squares per row, then do the same for height. Multiply the two together for the total — exactly what this calculator does.
Does joining shrink the square size slightly?
Yes, joining and blocking can pull squares in by a few millimeters. Measure a joined pair rather than a single blocked square if you want the most accurate count.
How do I size a granny square blanket for a specific bed size?
Check the Blanket Size Chart for standard dimensions, then enter that width and height here along with your square size to get the grid layout.