Half-Square Triangle Calculator
Design & CreativeCalculates the raw (unfinished) square size needed to cut and sew a half-square triangle quilt block to a given finished size.
Raw Square Size to Cut (in)
The unfinished square size to cut before sewing and trimming, including standard seam allowance.
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Creators
Odeh Ahwal0people find this calculator helpful
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Helpful
Saved
Embeds
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Frequently Asked Questions
Why add 7/8 inch?
A half-square triangle block needs a standard 7/8" (0.875") added to the finished size to account for the diagonal seam and 1/4" seam allowances on both resulting triangles -- a fixed offset used consistently across quilting patterns regardless of block size.
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