Fabric KG to Metres Calculator: The Short Answer
A brand buys 500 kilograms of single jersey that is 180 gsm and 150 centimetres wide in open width. Each metre weighs 270 grams, because 180 grams per square metre across 1.5 metres of width is 270. So one kilogram is 3.70 metres, and 500 kilograms is about 1,852 metres. At an illustrative £6.00 per kilogram, that is £1.62 a metre. The fabric kg to metres calculator does this arithmetic for any weight and width, in either direction.
The calculation is short, but it is easy to get wrong in practice because of the width. A tubular fabric quoted at 75 centimetres flat is 150 centimetres open, and mixing the two doubles or halves the answer. The calculator asks which kind you have for exactly this reason.
Used consistently, a fabric kg to metres calculator also protects the buyer from a quiet source of cost creep. If a repeat order arrives a little heavier or narrower than the first, the metres you receive per kilogram change, and so does the number of garments you can cut. Checking the yield on every delivery takes a minute and tells you early.
Use the Fabric KG to Metres Calculator
Choose the direction, enter the quantity and the finished fabric weight in gsm, and the fabric width in centimetres. Say whether the width is open or tubular. The fabric kg to metres calculator returns the length, the weight, the metres per kilogram and the weight of one metre. Add a price per kilogram to see the price per metre and the total for the quantity.
Fabric kg to metres calculator
Kilograms and metres
Assumes the stated gsm and width are the finished values. Allow for tolerance and shrinkage; the price per kg is your own input.
The finished values matter. Greige fabric, straight from the knitting machine, has a different weight and width from the same fabric after dyeing and finishing, so use the figures for the fabric you will actually cut. Ask the supplier for the finished gsm and the finished open width, and keep the fabric kg to metres calculator result with the purchase order.
The Formula Behind the Calculator
The weight of one metre of fabric is the gsm multiplied by the open width in metres. Dividing 1,000 grams by that weight gives the metres in a kilogram. Everything else is multiplication: metres in a quantity of kilograms, or kilograms in a length, follow directly.
From kilograms to metres
- 1Find the open widthDouble a tubular flat width; use an open width as it is.
- 2Convert to metresWidth in cm ÷ 100.
- 3Weight of a metregsm × open width in metres = grams per metre.
- 4Metres per kilogram1,000 ÷ grams per metre.
- 5Scale upMetres per kilogram × kilograms.
Standards bodies such as the ISO and AATCC publish test methods for fabric weight and dimensions, which is what a laboratory follows if you need a certified figure. For a budget, the finished values on the supplier's specification are enough.
How Fabric Weight Changes the Length per Kilogram
A heavier fabric gives fewer metres per kilogram, in direct proportion. The table fixes the width at 150 centimetres open and varies the gsm, and shows the metres in one kilogram and in 100 kilograms.
Metres per kilogram at 150 cm open width
| Fabric weight (gsm) | Metres per kilogram | Metres in 100 kg |
|---|---|---|
| 140 | 4.76 | 476 |
| 180 | 3.70 | 370 |
| 220 | 3.03 | 303 |
| 280 | 2.38 | 238 |
| 320 | 2.08 | 208 |
Calculated as 1,000 ÷ (gsm × 1.5). Illustrative fabric weights and a 150 cm open width.
Metres in 100 kilograms of fabric at 150 cm open width
Metres
Arithmetic: 100 kg × metres per kilogram. Illustrative fabric weights.
A switch from 180 to 280 gsm cuts the length you get per kilogram by more than a third. If two quotes are priced per kilogram, the heavier fabric needs more kilograms for the same garment, which matters for the true cost. Our GSM calculator checks the weight of a sample.
How Fabric Width Changes the Length per Kilogram
Width matters as much as weight. A wider fabric weighs more per metre, so you get fewer metres from a kilogram, but each metre covers more area. The table holds the gsm at 180 and varies the open width.
Metres per kilogram at 180 gsm by open width
| Open width | Metres per kilogram | Weight of one metre |
|---|---|---|
| 120 cm | 4.63 | 216 g |
| 150 cm | 3.70 | 270 g |
| 180 cm | 3.09 | 324 g |
Calculated as 1,000 ÷ (180 × width in metres). Illustrative widths.
Because the area per kilogram is constant for a given gsm, width does not change how many garments a kilogram makes. It changes how the pattern fits across the cloth, which is a layout question and is covered by the fabric consumption calculator.
Restating a Price per Kilogram as a Price per Metre
Knit fabric is priced per kilogram, but a designer or a pattern maker thinks per metre. The conversion is the price per kilogram multiplied by the weight of one metre in kilograms. At 180 gsm and 150 centimetres, one metre weighs 0.27 kilograms, so the table below applies.
Price per kilogram restated per metre (180 gsm, 150 cm open width)
| Price per kg | Price per metre |
|---|---|
| £4.00 | £1.08 |
| £5.00 | £1.35 |
| £6.00 | £1.62 |
| £7.00 | £1.89 |
| £8.00 | £2.16 |
Calculated as price per kg × 0.27 kg per metre. Example prices only, not market prices.
Always compare quotes at the same weight and width. A lower price per kilogram on a heavier or wider fabric can still cost more per garment. For quotes in yards, convert them with the yards to metres fabric calculator.
What Happens to a Kilogram After Cutting
Not every kilogram ends up in a garment. Wastage from cutting and end-of-roll loss takes a share, and the pie shows the split when 10 per cent is added to the garment weight.
Share of each kilogram bought that ends up in garments at 10% wastage
- In garments (909 g)90.9%
- Wastage (91 g)9.1%
Arithmetic: with 10% added for wastage, garments use 1 ÷ 1.1 = 90.9% of the weight. The wastage percentage is an illustrative assumption.
The pie is why a fabric budget should start from the garment weight and add wastage, rather than from the kilograms on the purchase order. Our guide to the cost of making a T-shirt shows fabric among the cost drivers.
A Worked Example: From Kilograms to T-Shirts
Pull the pieces together with the T-shirt from the fabric consumption calculator, which uses about 0.213 kilograms, or 0.79 metres, of 180 gsm fabric at 150 centimetres, including 10 per cent wastage. The 500 kilograms in the first example therefore make about 2,349 T-shirts, and the 1,852 metres give the same answer, because the two measures describe the same cloth.
The same 500 kg of fabric in four measures
| Measure | Quantity |
|---|---|
| Weight | 500 kg |
| Length at 150 cm open width | 1,852 m |
| Area | 2,778 m² |
| T-shirts at 0.213 kg each, including wastage | About 2,349 |
Arithmetic from the examples on this page and in the fabric consumption calculator. Illustrative measurements, with 10% wastage assumed.
Starting from kilograms and ending at garments is the most useful use of the fabric kg to metres calculator. It tells you how far a purchase will stretch, and whether the quantity on the order matches the size of the production run.
Rounding, Tolerance and Delivered Weight
Delivered fabric rarely matches the specification exactly. Weight and width carry tolerances, so a roll quoted at 180 gsm may arrive a few grams either side, and the metres you receive for a kilogram move with it. A difference of 5 gsm in 180 changes the length per kilogram by about 2.8 per cent, which on 500 kilograms is roughly 50 metres.
Record the weight and length of each delivery against the order. If the fabric is consistently heavy, you are paying for kilograms that give fewer garments, and if it is consistently light, the hand and drape may differ from the approved sample. Either pattern is worth raising with the supplier early, and the calculator gives you the figures to raise it with.
Tubular and Open Width: The Mistake That Doubles the Answer
Circular knitting produces a tube. Mills may sell the fabric as a tube, quoted by its flat width, or slit it open and quote the open width, which is about twice as much. A fabric quoted at 75 centimetres tubular is roughly 150 centimetres open. Treating the 75 as an open width makes the fabric look twice as long per kilogram.
Details to confirm about knit fabric quotes
- Whether the width is tubular or open
- Whether the gsm and width are greige or finished
- The tolerance on weight and width
- Whether the price is per kilogram of finished fabric
- How shrinkage after washing is handled
- Whether rib and trim fabrics are quoted separately
A general checklist. Your supplier confirms what applies to the fabric.
Fabrics that shrink change their finished width and weight, so plan for it with the fabric shrinkage calculator. Our guide to woven versus knit fabric explains why knits are usually sold by weight.
How Ruhrose Helps You Buy Knit Fabric Clearly
Ruhrose develops hoodies, fleece, jersey, denim and woven casualwear for UK buyers, with production in Bangladesh. We state fabric weights, widths and whether a width is open or tubular, so a quote is easy to compare and a sample is easy to check, and we sample before bulk. Ruhrose's clothing manufacturing pages show what we make.
Before you accept a fabric quote, ask yourself one question: do you know how many metres you are actually buying?