THE WARP PLANNING GUIDE

Count ends.
Keep the length honest.

A useful yarn estimate distinguishes the width you plan to put in the reed, the individual strands you will wind and the length already allowed for every strand.

Start with width in the reed

The width input is your planning width in the reed. It is not a prediction of finished cloth width, a yarn package width or a measurement between the centres of the first and last strands. Draw-in, finishing and the structure of your weave can change the relationship between a planned warp and the resulting cloth. Warpcount does not infer those changes from a yarn name or a weaving pattern.

Choose your width before using the calculator. For example, 25 cm and 250 mm represent the same physical width. Inches are converted using the exact relationship 1 inch = 25.4 mm. Selecting a different unit retains the original physical value internally; a direct edit replaces it with the number you actually enter in the currently selected unit.

Sett is an input, not a recommendation

Sett here means the number of individual warp ends per entered distance. You can enter ends per inch, often called EPI, or ends per 10 cm. These are densities, so the unit conversion is different from changing a plain length: 40 ends per 10 cm equals 0.4 ends per millimetre and 10.16 ends per inch.

Schacht Spindle’s weaving arithmetic guide relates in-reed width and EPI to warp end count, and separates winding length from finished length. Its weaving toolbox also treats sett and reed information as distinct planning resources. Those references provide context; this calculator does not choose a suitable sett, yarn, reed or threading arrangement.

If a draft specifies an end count or a particular repeat, check that information independently. This tool has one uniform entered density and a transparent arithmetic rounding rule. It does not adjust an end count to a pattern repeat, determine which dents to use or certify that the warp fits your loom.

Make the rounding rule visible

The body count starts with width multiplied by sett in matching units:

ideal body ends = width × ends per unit width
rounded body ends = ceiling(ideal body ends)
total individual ends = rounded body ends + extra individual ends

“Ceiling” means the smallest whole number at least as large as the ideal result. If the ideal body count is exactly 100, the rounded body count is 100. If it is 100.0000000001, the rounded count is 101. This is Warpcount’s cover-at-least planning policy, rather than a universal instruction for all weaving drafts.

At your entered sett, the rounded body count implies a body-only planning width equal to body count divided by density. Rounding upward can make this width slightly larger than the original target. The displayed implied width excludes extra ends. Extra selvedge strands may affect the physical arrangement, but their width contribution cannot be inferred from a count alone.

One original example, from width to stock

Leaving the available-yarn box empty produces “Unavailable”. It does not mean that you own no yarn. Entering zero is different: known zero stock gives a 306 m shortfall for this example. The distinction prevents an absent measurement from becoming a false stock claim.

Fractional widths can require another whole end

Consider an entered width of 8.125 inches and a chosen sett of 15 EPI. The ideal body count is 8.125 × 15 = 121.875 ends. The upward rule gives 122 body ends, adding 0.125 to the ideal count. With two extra individual ends, the total becomes 124.

If every end has a total winding length of 84 inches, the required length is 124 × 84 = 10,416 inches. At exactly 0.0254 metres per inch, this is 264.5664 m. The calculation does not first round the per-end length or multiply a rounded yard conversion. At 15 EPI, the 122 body ends imply 122 ÷ 15, or approximately 8.1333333333 inches, of body-only planning width.

An end is one strand

Count each extra strand individually. A floating selvedge can add an individual end, while a doubled arrangement can involve more than one strand. Warpcount does not infer the number from a technique name. Enter the additional strand count that belongs to your actual plan.

A folded loop includes two strand lengths. Do not enter a number of folded loops as though it were the number of individual ends. Likewise, the length-per-end field is for one individual strand, not the combined length of a doubled loop. Making both choices explicit avoids a factor-of-two error that a neat-looking total could otherwise conceal.

Put allowances into the winding length once

The per-end length is already the total length you intend to wind for one strand. Decide how you are accounting for finished project length, take-up, shrinkage, fringe, sampling, loom waste and other needs before entering it. This site adds none of those automatically, so it cannot secretly count a chosen allowance twice.

If your total planned winding length is 3 m per individual end, enter 3 m even if the finished piece is intended to be shorter. Do not add the same waste length again after reading the total. If your plan changes, revise the per-end length and recalculate. Uniform length is assumed; for differently sized groups, calculate and record the groups separately rather than pretending all strands have the same length.

Compare stock with the same scope

The optional stock input is the usable yarn length you choose to allocate to this warp. It is not a mass input and the calculator does not derive length from an unentered metres-per-gram figure. A ball label, partial package or weighed sample can carry uncertainty that this arithmetic cannot resolve.

Exclude yarn reserved for weft or another project before entering available warp stock. A positive balance is a surplus under your inputs, a negative balance is a shortfall and zero is an exact arithmetic match. Knots, breaks, joins, unusable remnants and actual yarn behaviour can still affect what you can use. The tool does not assess tensile strength, abrasion resistance, suitability or real-world loom capacity.

Exact decisions, readable displays

Decimal entries are stored as exact fractions for multiplication, unit conversion, upward rounding and stock comparisons. Whole-number decisions are not made from a rounded display or a small numerical tolerance. The width 100 mm at 40 ends per 10 cm gives exactly 40 body ends; a width of 100.0000000001 mm gives 41. Repeated unit-only changes preserve the original value behind the display.

Plain decimals and decimal scientific notation such as 1e-3 are accepted, with a maximum of 100 characters, 60 coefficient digit characters (including leading zeros) and an exponent from −100 to 100. Commas, attached unit letters and hexadecimal notation are rejected. Width and per-end length must be positive, with upper limits of 10,000 mm and 10,000 m respectively. Stock must be nonnegative and no greater than 10 billion metres. Extra ends must be a whole number; total individual ends cannot exceed 1,000,000. These are software limits, not weaving recommendations.

Converted input displays may be rounded to sixteen significant digits, and result displays are rounded for reading. The retained exact values govern the answer until you edit an entry. Text and CSV exports include canonical fractions and their units so that a tiny difference is not lost. A fraction such as 1/3 means exactly one third; a displayed decimal approximation does not imply more accuracy in your measurement.

Keep a local record, then check the plan

Copy, text and CSV reports are generated locally in your browser. They include the width and density in canonical units, ideal and rounded body counts, extra individual ends, winding length, total warp yarn and the stock state. The diagram is a proportional summary of the count, not a threading draft, reed plan, print template or loom setup instruction.

If an active entry becomes invalid, usable results and the diagram are cleared and exports are disabled. Restore example returns to the known 25 cm example with stock left unknown. There is no account, saved project or hidden upload service. You choose whether to keep an exported file or share it yourself. Return to the calculator.