QST-Rechner 🔷
Calculate cutting sizes for Quarter Square Triangle (QST) blocks. Enter finished size and unit count to get exact cut square size and squares needed.
How to Use the QST Calculator
Enter the finished size of your QST unit (the finished square after all seaming) and how many units your pattern needs. The calculator returns the cut square size and the number of squares to cut.
To cut: mark and cut each square to the size shown, then cut it diagonally in both directions (X cut) to yield 4 triangles. Pair contrasting triangles and sew to form hourglass/QST units. One square = 2 finished QST units.
QST triangles are cut on the bias and stretch easily. Starch the fabric lightly before cutting, press seams carefully, and square up each unit with a specialty ruler for best accuracy.
Häufig gestellte Fragen
What is a Quarter Square Triangle (QST)?
A QST is made by cutting a square diagonally in both directions (X cut), yielding 4 triangles. Two QST triangles sewn together form a hourglass unit. Used in Ohio Star, Pinwheel, and many other classic blocks.
What is the QST cutting size formula?
QST cut square = finished size + 1.25". For a 6" finished unit, cut at 7.25". One square yields 4 triangles = 2 QST units.
What is the difference between HST and QST?
HST is cut once diagonally (2 triangles, 1 seam per unit). QST is cut twice diagonally — X cut (4 triangles, each unit needs 2 triangles from different squares).