HST Quilt Calculator
The calculator helps quilters find fabric square sizes for Half Square Triangles (HSTs).
Enter finished HST size, click “Calculate”.
Results show square sizes for 2-at-a-time, 4-at-a-time, and 8-at-a-time methods.

What is Half Square Triangle in quilting?
In quilting, a half-square triangle (HST) is a unit made by stitching two right-angled triangles together to form a square.
There are several ways for making HSTs, including 2-at-a-time, 4-at-a-time, and 8-at-a-time, which make varying amounts of HST units at once.
HSTs are a frequent unit in quilting patterns and are exceedingly adaptable, serving as the foundation for many quilt pieces.
How to calculate the Quilt Half Square Triangles?
Here is how you can calculate the Quilt HSTs:
To calculate 2-at-a-time:
Square Size = Finished HST Size + 1
To find out 4-at-a-time
Square Size = (Finished HST Size + 0.5) * √2 + 0.5
To find out 8-at-a-time:
Square Size = Finished HST Size * 2 + 2

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