Square in a Square Quilt Block — Cutting Chart by Finished Size

2 fabrics · Difficulty 3 of 5

Square in a Square is a 1×1 block of 5 pieces. Cut sizes for 4″, 8″, 12″, 16″, 20″ are below; for any other size it divides into cleanly, type the size and the chart recomputes.

Accepted finished sizes must resolve to ruler-compatible cuts; unsupported sizes are refused with nearby clean sizes and are never silently rounded.

At a glance

Grid

1×1

Pieces you cut

3 — subcutting turns them into the 5 in the sewn block

Difficulty

3 of 5 — confident beginner · How this is scored

Which sizes divide cleanly

Scroll sideways to see every column.

• A 5-patch block at 12″ would need 2.4″ units, which is not a mark on any ruler. Try 10″ or 12½″ instead — Sister's Choice is the 5-patch block on this site.
• A 7-patch block at 12″ would need 1.714…″ units, which is not a mark on any ruler. Try 10½″ or 14″ instead — Bear's Paw is the 7-patch block on this site.

More about the sizes that do not divide cleanly

The sizes in between

Every whole-inch Square in a Square size from 4″ to 20″ can be cut accurately on its 1×1 grid.

These sizes divide cleanly but sit between the main chart's columns — the same computed cuts, published here so they exist on paper too. Any other clean size still computes in the size input above.

Column headings are the FINISHED block size — the size it will be once it is sewn. Every number in the table is the size to CUT, which includes ¼″ of seam allowance on each edge. Rows that are subcut on a diagonal are cut larger still, so the allowance survives the extra cuts.

Scroll sideways to see every size.

About this block

Pieces in the finished block

5

Unit types

square-in-a-square unit

Divides cleanly at

½″, 1″, 1½″, 2″, 2½″, 3″, 3½″, 4″, 4½″, 5″, 5½″, 6″, 6½″, 7″, 7½″, 8″, 8½″, 9″, 9½″, 10″, 10½″, 11″, 11½″, 12″, 12½″, 13″, 13½″, 14″, 14½″, 15″, 15½″, 16″, 16½″, 17″, 17½″, 18″, 18½″, 19″, 19½″, 20″, 20½″ and 21″ finished.

Also known as

Square in Square, Diamond in a Square

Fabric for one 12″ block

This is a conservative buying estimate for one cut size at a time: ½ yd total, assuming 40″ of usable width of fabric; different cut sizes are not co-packed, and purchase length is rounded up to the next eighth yard.

One unit is the entire block: a centre square set on point inside corner triangles, no internal grid at all. The centre's corners must land at the midpoint of each side, and its points need seam allowance preserved beyond them when the block joins the top. The corner triangles' long edges are bias — sew them without stretching and press away from the centre.

Piecing order

1. Make the 1 square-in-a-square unit.

2. Lay out row 1 of 1 and sew its pieces together, left to right.

Cutting oversize

The chart gives the standard cut sizes, nothing padded. Some quilters cut this block's triangle units a little oversize and trim back — published allowances genuinely disagree on how much, so the range with its sources is on how to square up a quilt block.

History

The exact model on this page is a centre plus one round of triangles. Economy is a close two-round relative, and naming overlaps in use: sources apply Square in a Square, Diamond in a Square and Economy-family names across related constructions.

Sources: Generations Quilt Patterns — Economy Block; Scrapish — Economy Block.

Common questions