Fabric Consumption per Garment Calculator

The formula

This is the expression the tool evaluates. Every term is named underneath, with the unit it must be supplied in.

How the result is derived

Step by step, from the values you type to the figure on screen.

1. Marker length per garment already includes marker efficiency: it is the total marker divided by the number of garments in it, so the in-marker waste is inside the number rather than added afterwards.
2. Area times GSM gives the net mass. This is the fabric that ends up in the garment plus the marker waste.
3. End loss covers what the spreading table cannot use: end bits, splices, roll ends and the leading and trailing allowance on each lay.
4. Shrinkage allowance covers fabric relaxed or washed before cutting, and any residual shrinkage the pattern has to absorb.
5. The reject allowance covers garments cut and sewn but never shipped. It is applied last because a rejected garment wastes fabric that had already carried every earlier allowance.

What each input means

Where to read each value on the floor, the unit it must be in, and the range the tool accepts.

What the tool returns

The headline figure and every supporting value it is built from.

Worked example

Substituting

Adding the three allowances instead of compounding them would give 1.1000 and under-book the order by 0.3%. On 100,000 garments that is 140 kg of fabric nobody costed.

How to use it

1. Work through the input groups in order — Marker Yield and Allowances. The defaults are a realistic case, so you can change one value at a time and watch what moves.
2. There is no calculate button. Every figure recalculates as you type or drag, which is what makes this usable for a what-if sweep rather than a single answer.
3. Read Fabric per Garment in the dark results panel — that is the headline figure, expressed in kg.
4. Check the supporting rows underneath (Net Fabric in Garment, Fabric Length per Garment, Fabric per Garment and Combined Allowance Factor) before acting on the headline — they are where an implausible input usually shows itself first.
5. Reset to defaults returns every field to the reference case, which is the quickest way to check whether a surprising result came from the tool or from an input you had changed earlier.

Where this is used

• Fabric booking — turning an order quantity into the kilograms or metres to place on the mill, in the unit the mill invoices in.
• Costing — fabric is usually 55% to 70% of the cost of a basic garment, so the allowance factor is where a thin margin is won or lost.
• Cut plan review — comparing the booked consumption against what the cutting room actually used, and attributing the gap to marker, spreading or rejects.
• Style comparison — testing whether a wider fabric or a different marker plan pays for itself before the order is placed.

Reading the result

Typical bands and what each one is telling you.

Assumptions and limits

• Knits are booked by weight and wovens by length. Quote in the unit the mill invoices in, or the reconciliation will never close.
• Every input is bounded to the range normal practice occupies (Marker Length per Garment 0.01 to 50 m, Usable Fabric Width 0.1 to 5 m and Fabric Weight 10 to 1000 g/m², and so on for the rest). Those bounds are guard rails against typing errors, not a claim that the formula fails one unit outside them.
• The calculation is deterministic: the same inputs always give the same result. It carries no allowance for machine condition, operator skill, ambient conditions or lot-to-lot material variation unless an input above explicitly represents one.
• Nothing is sent anywhere. The maths runs in your browser, so the numbers you type never leave the page.

Standards and further reading

• ASTM D3773 — fabric length measurement, which decides what the roll actually contains.
• AATCC 135 / ISO 6330 — dimensional change on washing, the source of the shrinkage allowance.
• ASTM D3776 / ISO 3801 — mass per unit area, the GSM input.

Questions people ask