Quilting Calculator App | Designed to Quilt (2024)

The T-Shirt Quilt calculator calculates the layout of your T-Shirt quilt based on the dimensions of T-shirt blocks you’re using, the desired quilt size, and the desired sashing. If required, it will also calculate sashing borders and cornerstones.

See the diagram below for an explanation of the layout elements. Quilt Geek will also provide an illustrated diagram based on the options you select.

T-SHIRT QUILT BLOCKS (pale color)
Quilt blocks cut from your T-shirts.

SASHING (orange color)
Strips placed horizontally and vertically among quilt blocks.

SASHING BORDERS (blue color)
Sashing strips placed around the quilt layout (along the edges of the finished quilt top).

INNER CORNERSTONES (yellow color)
Small contrasting squares in the sashing at the corners of the blocks.

OUTER CORNERSTONES (pink color)
Small contrasting squares in the sashing borders at the corners of the blocks.

The math behind a T-shirt quilt is pretty much the same as the math for any block-based quilt. Just that instead of quilt blocks, you’ll be using pieces of fabric cut out from your favorite T-shirts. The first thing you’ll need to do is gather the T-shirts that you want to use and measure what size your T-shirt blocks can be. Usually, you want to go as large as possible to make use of that fabric.

EXAMPLE
Let’s say we’re using men’s XL T-shirts and we can cut out blocks measuring 14.5 x 14.5”. This means we’ll get 14 x 14” FINISHED blocks. We want to add 4” (finished) sashing between the blocks and sashing border. We’re aiming for a lap-size quilt.

Enter the numbers into the calculator. Numbers from the example are written in (parentheses).

UNFINISHED WIDTH OF T-SHIRT BLOCKS (14.5)
Width (horizontal dimension) of the T-shirt blocks you are using measured before they are sewn in the quilt top (the width of units you cut from the T-shirts).

UNFINISHED HEIGHT OF T-SHIRT BLOCKS (14.5)
Height (vertical dimension) of the T-shirt blocks you are using measured before they are sewn in the quilt top (the height of units you cut from the T-shirts).

There are various layout options for your T-shirt quilt. Select your desired layout, and Quilt Geek will provide an illustrated diagram based on your choices.

If you want to add sashing, keep YES selected and enter the numbers. If you prefer to make a T-shirt quilt without sashing, select NO, and the other options will close.

EXAMPLE
In our sample quilt, we want to add 4″ finished sashing and are using a 42″ WOF. We would like to have sashing borders (YES), without inner cornerstones (NO), and without outer cornerstones (NO). We’re aiming for lap size quilt.

FINISHED SASHING WIDTH (4)
Width of the sashing measured on the finished quilt top (without seam allowances).

WIDTH OF FABRIC (WOF) FOR SASHING (42)
Width of the fabric you are using, measured from one selvage edge to the other.

APPROXIMATE QUILT SIZE (LAP SIZE)
Approximate size of the quilt you want to make. The calculator uses standard quilt sizes – see assumptions.

Quilt Geek provides a list of all the important numbers you need to make your T-shirt quilt.

YOUR QUILT:
NUMBER OF T-SHIRT BLOCKS (6)
Total number of T-shirt blocks in your quilt layout.

NUMBER OF COLUMNS OF BLOCKS (2)
Number of columns in your quilt layout – How many blocks are there across the quilt?

NUMBER OF ROWS OF BLOCKS (3)
Number of rows in your quilt layout – How many blocks are there down the quilt?

FINISHED QUILT WIDTH (40)
Finished width of the quilt top including the sashing.

FINISHED QUILT LENGTH (58)
Finished length of the quilt top including the sashing.

SASHING:
TOTAL SASHING LENGTH (339)
Total length of strips required for the sashing.

NUMBER OF CORNERSTONES (not used in our sample quilt)
Total number of cornerstones in your quilt layout.

WIDTH OF WOF STRIPS TO CUT (4 ½)
Width of strips you need to cut from your fabric for sashing/cornerstones (= unfinished sashing/cornerstone width).

NUMBER OF WOF STRIPS TO CUT (9)
Number of strips you need to cut from your fabric for sashing/cornerstones.

TOTAL YARDAGE (& METERAGE)
Fabric requirements are in inches and in yards (and in meters, if meterage is turned on in Settings). Values in inches are rounded up to the nearest ⅛ (0.125) inch. Values in yards are rounded up to the nearest ⅛ (0.125) or ⅓ (0.333) yard. Values in meters are rounded up to two decimal places.

* ASSUMPTIONS
The calculator automatically adds the seam allowance required to join the sashing strips with diagonal seams. The calculator uses standard quilt sizes found in the Standard Quilt Size Chart as a reference.