Warp Calculation Calculator

Warp length from finished size, loom waste, and shrinkage.

Finished length (inches)

Loom waste (inches)

Take-up %

Shrinkage %

Warp width (inches)

Ends per inch (EPI)

Tab to move between fields

Total warp length (inches)

73.7

Total warp yarn (yards)

491

Total warp length (yards)2

Total warp ends240

Waste percentage36.6%

How to Use This Calculator

Enter the desired finished length of the fabric in inches.
Set the loom waste in inches (typically 18–36 in depending on loom type).
Enter take-up percentage (warp shortening from weft interlacement; plain weave ~10%).
Enter shrinkage percentage (length lost after wet-finishing; cotton ~5–8%, wool ~10–15%).
Enter the warp width in inches on the loom and the EPI for your sett.
Read the total warp length per thread in inches and yards, total ends, and total warp yarn yardage needed.

How the result changes with Finished length (inches)

Finished length (inches): Desired finished length of the woven fabric in inches.
Loom waste (inches): Unweavable warp at front and back of loom. Typically 18-36 inches depending on loom type.
Take-up %: Warp shortens as weft interlaces. Plain weave ~10%, twill ~8-12%.
Shrinkage %: Length lost after wet-finishing. Cotton ~5-8%, wool ~10-15%.
Warp width (inches): Width of the warp on the loom (wider than finished width due to draw-in).
Ends per inch (EPI): Number of warp threads per inch, determined by sett.

Total warp length (inches): Total length of each warp thread to wind, including all allowances.
Total warp length (yards): Same measurement converted to yards.
Total warp ends: Total number of individual warp threads across the width.
Total warp yarn (yards): Total yardage of warp yarn needed for the project.
Waste percentage: Percentage of total warp length lost as loom waste.

Identify Input Parameters
4 parameters
Finished length (inches) = 36, Loom waste (inches) = 27, Take-up % = 10, Shrinkage % = 5 = 6 input(s) provided
Calculate Total warp length
Total warp length = (finishedLength + loomWaste) / max(0.01, takeUpFactor) / max(0.01, shrinkageF...
73.7 = 73.7
Calculate Total warp yarn
Total warp yarn = totalEnds * totalWarpLengthYards
491 = 491
Calculate Total warp length
Total warp length = totalWarpLengthInches / 36
2 = 2
Calculate Total warp ends
Total warp ends = round(warpWidth * epi)
240 = 240