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YardageLab

Quilt Size Calculator

Turn a block size and layout into finished quilt dimensions and the closest standard bed size.

Units
in

The size of one block after it is sewn into the quilt.

blocks
blocks
in

Between blocks. 0 = none.

in

Each side. 0 = none.

Finished quilt size

60 × 72in

Closest standard size: Throw / Lap

Width
60 in
Length
72 in
Total blocks
30
5 × 6 = 30 blocks
Assumptions used
Finished block size
12 in
Grid
5 across × 6 down
Sashing between blocks
none
Border each side
none

Methodology

How the size calculation works

The finished quilt is the sum of its blocks, the sashing between them and the borders around the outside:

  • Width = (blocks across × block size) + sashing between blocks + (2 × border)
  • Length = (blocks down × block size) + sashing between blocks + (2 × border)

Sashing sits between blocks, so a row of five blocks has four sashing strips. We then compare your finished size to standard US quilt sizes and show the closest match.

See it in numbers

Worked example

12″ blocks in a 5 × 6 grid, no sashing or border:

  • Width = 5 × 12 = 60″
  • Length = 6 × 12 = 72″
  • 30 blocks total → closest standard size: Throw / Lap

Reference

Standard US quilt sizes

SizeApprox. widthApprox. length
Baby / Crib36 in52 in
Throw / Lap52 in60 in
Twin70 in90 in
Full / Double84 in90 in
Queen90 in100 in
King108 in100 in

Sizes vary by mattress depth and desired drop — treat them as a starting point.

Frequently asked questions

Should I use finished or unfinished block size?
Use the finished block size — the size after the block is sewn into the quilt (typically ½″ smaller than the unfinished block on each dimension).
Does sashing go around the outside too?
This tool places sashing only between blocks. For sashing around the outside edge as well, add that amount to the border field.
How do I plan the backing once I know the size?
Take the finished width and length into the quilt backing calculator to get backing yardage, and the binding calculator for the edge.

Transparency

Sources & assumptions

  • Uses finished block dimensions.
  • Sashing is counted between blocks only.
  • Borders are added equally to all four sides.
  • Standard sizes are approximate and depend on mattress and drop.

Keep planning

Related calculators

Quilt Backing CalculatorWork out how much backing fabric to buy, how many panels to cut and which way the seam should run.Quilt Binding CalculatorFind the binding length, number of strips and fabric you need to bind the edge of your quilt.Fabric Yardage CalculatorCalculate how much fabric to buy for any number of same-size pieces, laid out to waste as little as possible.

Last reviewed August 23, 2026

Found an error? Tell us — every formula is human-reviewed.