Piecing Calculators
Know your blocks and triangles before you cut. Work out block layouts, triangle cut sizes and how many pieces you need, plus sashing and setting triangles, so every piece fits the first time.
All piecing calculators
Pick the block or triangle you are working on. Each calculator shows its working, so you can check every number yourself.
Quilt Block Size Calculator
Blocks and layout for a quilt top, from target size and block size, with no sashing.
Calculate block size →Quilt HST Calculator
Half-square triangles by the two-at-a-time method, cut size equals finished size plus 7/8 inch.
Calculate HSTs →Quilt Flying Geese Calculator
No-waste flying geese, where finished width is twice finished height, with large and small cut squares.
Calculate flying geese →Quilt QST Calculator
Quarter-square triangles by the two-square method, cut size equals finished size plus 1 and 1/4 inch.
Calculate QSTs →Quilt Half-Rectangle Calculator
Half-rectangle triangles by the oversize and trim method, cut size equals finished size plus 1 inch in each direction.
Calculate half-rectangles →Quilt Square in a Square Calculator
Center square set on point inside a block, center cut size from finished size divided by 1.414.
Calculate square in a square →Quilt Sashing Calculator
Sashing strips between blocks, with continuous vertical strips and no cornerstones.
Calculate sashing →Quilt Setting Triangles Calculator
Side and corner setting triangles for on-point layouts, sized from block size, with no sashing between blocks.
Calculate setting triangles →No calculator matches that search yet. Try “hst”, “flying geese” or “sashing”.
Piecing guides
Learn the method behind the numbers, before you cut.
How to Calculate Block Size
Block size and layout, target size versus finished size, and how to choose a layout.
Read guide →How to Calculate HST
Half-square triangles step by step, with the two-at-a-time cut size and counting rules.
Read guide →How to Calculate Flying Geese
No-waste flying geese step by step, with large and small squares and extra geese explained.
Read guide →How to Calculate QST
Quarter-square triangles step by step, and how QST cut sizes differ from HST cut sizes.
Read guide →How to Calculate Half-Rectangle
Half-rectangle triangles step by step, with oversize and trim and why trimming is required.
Read guide →How to Calculate Square in a Square
Square in a square step by step, with center and corner cut sizes and trimming to unfinished size.
Read guide →How to Calculate Sashing
Sashing between blocks step by step, with strip counts, cornerstones, and borders explained.
Read guide →How to Calculate Setting Triangles
Setting triangles step by step, with side triangles, corner triangles, and on-point layouts explained.
Read guide →