Calculate cutting sizes for quilting HSTs.
Last updated: June 2026 | By Patchworkr Team
The calculator adds the seam allowance needed for either the traditional 2-at-a-time method or the Magic 8 approach.
Use Magic 8 when you need many identical HSTs quickly.
Finish size 3" using Magic 8 for 16 HSTs.
1. Cut size = 3 + 1.25 = 4.25
2. Squares needed = ceil(16/8) x 2 = 4
3. Total HSTs made = 16
Final answer: cut 4 squares at 4.25"
Can I enter decimals?
Yes. Finished size can be a decimal value.
What does efficiency mean?
It is the ratio of needed HSTs to total HSTs produced.
Why is Magic 8 faster?
It creates eight units per two squares, reducing cutting steps.
Is the fabric yardage exact?
No. It is a quick estimate.
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