Square in square calculator

Square in a Square Calculator


The Square-in-a-Square calculator is a helpful tool for quilters and fabric crafters that makes it easy to figure out the size of a square-in-a-square quilt block, which is also called a diamond-in-a-square block.

This block design has a square in the middle that is surrounded by four triangles.

This makes the square in the middle look like it is set on point. Finding the right sizes for cutting fabric pieces to make these quilt blocks is easier with the help of the calculator.

Calculator and formula to calculate square in a square block

Use Cases:

  1. Making quilt blocks for several quilt patterns that use the square-in-a-square design.
  2. To calculate dimensions for sewing square-in-a-square quilt blocks of varied sizes.
  3. Helping beginners in understanding the fabric proportions needed for this specific quilt block.

How to Use the Square-in-Square Calculator?

  1. Choose the first dimension from the dropdown menu. You have the option of selecting “Finished Size” (the size of the finished quilt block) or “Huge Square Size” (the size of the initial large square).
  2. Input the desired starting dimension’s length (in inches).
  3. To calculate the dimensions of the large and tiny squares, click the “Calculate” button.
  4. In their respective fields, the estimated results for the large and small squares will be shown.

Formula to calculate the square in square

  1. When starting with the “Finished Size”:
    • Large Square Size = Finished Size + 0.5
    • Small Square Size = (Finished Size / 2) + 0.5
  2. When starting with the “Large Square Size”:
    • Finished Size = Large Square Size – 0.5
    • Small Square Size = (Finished Size / 2) + 0.5

These formulas use a 0.5-inch seam allowance, which is important for sewing the quilt block pieces together.

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