Quilt Numbers

Fat Quarter Calculator: How Many Cut Pieces Fit?

By Tam Vu · Updated

On this page
  1. How the count works
  2. Measure the actual cut
  3. Source

A fat quarter is a half-yard cut in half across the usable fabric width: 18 in long by half the usable width. With 42 in of usable width, that works out to 18 × 21 in. If your fabric is narrower, the fat quarter's other dimension is narrower too.

Pieces from a fat quarter

This estimates a clean rectangular cut layout. It does not add seam allowance to your entered cut-piece dimensions or account for shrinkage, print direction, defects or squaring the cut.

How the count works

The calculator checks both orientations. For each one, it divides the fat quarter's 18 in side and half-width by the cut-piece sides, rounding each count down to whole pieces. It selects the orientation that fits more pieces, then divides the number you need by that capacity and rounds up to whole fat quarters.

Usable width Fat quarter size Cut piece Fit per fat quarter (best orientation)
42 in 18 × 21 in 5 × 5 in 12
42 in 18 × 21 in 3 × 7 in 18, rotated
40 in 18 × 20 in 4 × 6 in 15

For 25 pieces measuring 5 × 5 in from 42 in fabric, 12 fit in one fat quarter, so plan on 3 fat quarters. The third cut leaves some capacity unused. Each cut piece's dimensions should already include whatever seam allowance your pattern calls for.

Measure the actual cut

Fat-quarter dimensions can vary with the usable width and how the cut is prepared. Measure the piece you have, especially after trimming the selvage or prewashing. If the pattern uses long strips or directional prints, draw the cutting layout before relying on the rectangular count.

Source

  • Fat-quarter dimensions follow the assumption stated above: 18 in by half the usable fabric width. Layout counts use rectangle packing; 1 yd = 36 in.