Weaving Warp & Weft Yardage Calculator
Enter the finished size, sett, take-up, shrinkage, draw-in, loom waste, and package lengths. The calculator works backward to estimate warp and weft yarn before you wind the warp.
Total project yarn (yd)763.09
- Width in the reed (in)
- 13.3
- Total warp ends
- 160
- Warp length per end (in)
- 106.65
- Total warp yarn (yd)
- 474
- Total weft yarn (yd)
- 289.09
- Warp yarn packages
- 1
- Weft yarn packages
- 1
Planning breakdown
| Planning item | Value | Unit |
|---|---|---|
| Finished length per piece | 60 | in |
| Pre-shrink woven length per piece | 63.16 | in |
| Warp cloth length after take-up per piece | 68.65 | in |
| Warp take-up allowance per piece | 5.49 | in |
| Fringe allowance per piece | 8 | in |
| Loom waste plus sampling | 30 | in |
| Pre-finish cloth width | 12.63 | in |
| Width in the reed | 13.3 | in |
| Raw end count | 159.56 | ends |
| Repeat-rounding adjustment | 0.44 | ends |
| Total picks | 758 | picks |
| Weft path per pick | 13.73 | in |
Sett values are interpreted per inch; yarn totals are reported in yd.
Package counts are rounded up only when the corresponding package length is greater than zero.
The estimate divides backward through take-up and shrinkage, then adds fixed warp allowances.
How to use this calculator
- Choose inches and yards or centimeters and meters, then keep every measurement in that system.
- Enter the finished size, number of pieces, fringe, warp sett, weft sett, and threading repeat.
- Add take-up, shrinkage, draw-in, loom waste, and sampling allowances from your loom or sample.
- Use the yarn totals and package counts to plan winding, buying, or cone allocation.
How the yarn estimate is calculated
This calculator plans from the finished cloth backward. It first restores the length and width lost during finishing, then restores the extra yarn consumed by take-up. Fixed warp allowances, such as loom waste and sampling length, are added after the cloth length is adjusted.
Let FL be finished length per piece, FW be finished width, N be the number of pieces, and E be fringe at each end. Decimal loss rates are sL = length shrinkage / 100, sW = width shrinkage / 100, tW = warp take-up / 100, tF = weft take-up / 100, and d = draw-in / 100.
The pre-finish woven length per piece is:
OL = FL / (1 - sL)
The warp length consumed by that cloth is:
WC = OL / (1 - tW)
The warp length to wind for each end is:
WL = N x (WC + 2 x E) + loom waste + sampling allowance
Width is handled separately because width shrinkage and draw-in happen across the cloth. The pre-finish cloth width is CW = FW / (1 - sW), and the width in the reed is RW = CW / (1 - d). Raw warp ends are RW x warp sett, then the result is rounded up to a complete threading or color repeat.
Total warp yarn is WL x rounded ends, converted from inches to yards or from centimeters to meters. Total picks are ceiling(N x OL x weft sett). Each pick uses CW / (1 - weft take-up) of yarn, so total weft yarn is total picks times that adjusted pick length, converted to the selected yarn unit.
What moves the result most
Width and sett usually dominate warp yardage because every extra end carries the full warp length, including loom waste and sampling. Loom waste matters most on small projects because it is multiplied by every end even though it never becomes cloth.
Weft yardage is driven by picks per unit, cloth width before finishing, and weft take-up. A small change in beat can add many picks across a long warp, while a wider pre-finish cloth increases the length of every pick.
What this calculator leaves out
The estimate assumes a rectangular project with the same sett, width, pick density, take-up, and shrinkage throughout. It does not model decorative borders, tapestry packing, pile, clasped weft, supplemental warps, differential-length warps, repairs, knots, color matching, or unusable yarn left on separate cones.
Measured numbers from a washed sample are better than defaults. Take-up, draw-in, and shrinkage can change with yarn, structure, beat, tension, finishing method, and loom setup.
Worked example
Suppose you plan one scarf that should finish at 12 inches wide and 60 inches long, with 4 inches of unwoven fringe at each end. The warp and weft setts are both 12 per inch, the threading repeat is 1 end, warp take-up is 8%, weft take-up is 8%, length and width shrinkage are both 5%, draw-in is 5%, loom waste is 24 inches, and sampling allowance is 6 inches.
The finished length is divided by 0.95, so the pre-finish woven length is 63.158 inches. Dividing that by 0.92 gives 68.650 inches of warp consumed by the cloth. After fringe, loom waste, and sampling, each warp end is 106.650 inches long.
The finished width is divided by 0.95 for shrinkage and again by 0.95 for draw-in, giving a reed width of 13.296 inches. At 12 ends per inch, that rounds up to 160 warp ends. Total warp yarn is about 474.0 yards, total weft yarn is about 289.1 yards, and the project total is about 763.1 yards. With 840-yard packages for both warp and weft, the calculator reports one package for each.
Common questions
How do I calculate warp length for several towels on one warp?
Enter the finished length for one towel and set the number of pieces to the number of towels. The calculator applies the cloth length and two fringe allowances to every piece, then adds loom waste and sampling once for the whole warp.
What is the difference between take-up, draw-in, and shrinkage?
Take-up is yarn consumed by interlacement as warp and weft bend around each other. Draw-in is the width lost at the loom as the edges pull inward. Shrinkage is the size lost during finishing after the cloth is removed from the loom.
Why are take-up and shrinkage divided out instead of simply added?
The entered percentages describe losses from a longer or wider starting state to the finished state. Dividing by the retained fraction reverses that loss. Adding the percentages can understate the needed length or width, especially when several losses compound.
Should fringe be included in finished length?
No. Enter the finished woven cloth length without unwoven fringe, then enter fringe separately as the allowance at each end. The calculator adds two fringe allowances for each piece on the warp.
Why does the calculator round warp ends to a threading repeat?
Many drafts and stripe sequences only work when the warp ends complete a repeat. The calculator rounds the raw end count upward so the planned warp does not stop in the middle of a threading or color sequence.
How can I measure take-up and shrinkage from a sample?
Mark or measure the sample on the loom, then measure it again after wet finishing. Compare woven length before finishing with finished length for length shrinkage, reed or on-loom width with later width for draw-in and width shrinkage, and yarn consumed with straight cloth dimensions for take-up.