If you compare two jute bag quotations and one is 20% cheaper, the fabric weight is the first place to look. It is the largest single cost in the bag, it determines almost everything about how the finished product feels, and it is the easiest thing for a supplier to quietly reduce. This guide explains what the number means, how to convert it, and which weight to specify for what.
- Jute weight is quoted in ounces per square yard. Multiply by 33.9 to get grams per square metre.
- 10 oz is the retail tote default. 12 oz for grocery and heavy loads. 7–8 oz for promotional giveaways only.
- Two fabrics at the same weight can differ a lot — ask for porter and shots, not just oz.
- A quotation without a stated fabric weight is not a quotation. Ask before you compare prices.
What "oz" actually measures
Jute fabric — hessian, or burlap in American usage — is traditionally specified in ounces per square yard. A 10 oz fabric weighs ten ounces for every square yard of cloth, regardless of how wide the roll is.
This trips people up because most other textiles are specified in GSM (grams per square metre), and because "oz" sounds like it might be a thickness. It is not. It is areal density: how much fibre is packed into a given area. More fibre per area generally means a stronger, stiffer, more opaque fabric that costs more and weighs more in a container.
Weight is not the whole story — a loosely woven heavy yarn and a tightly woven fine yarn can hit the same number and behave differently — but it is the single best summary of a jute fabric, which is why every serious specification starts with it.
Oz to GSM: the conversion
One ounce per square yard equals 28.3495 g divided by 0.8361 m², which is 33.9 g/m². So the conversion is simply the oz figure multiplied by 33.9.
| Weight (oz/yd²) | Approx. GSM | Character | Typical use |
|---|---|---|---|
| 7 oz | 237 | Light, soft, slightly translucent | Promotional giveaways, drawstring pouches, sleeves |
| 8 oz | 271 | Light but opaque | Folding shoppers, low-cost retail bags, gift pouches |
| 9 oz | 305 | Mid-weight, drapes well | Lined totes where the lining adds body |
| 10 oz | 339 | The workhorse. Holds shape, prints cleanly | Retail totes, wine carriers, conference satchels |
| 11 oz | 373 | Firm, structured | Heavier totes, bags with base boards |
| 12 oz | 407 | Stiff, hard-wearing | Grocery shoppers, laptop bags, hampers |
| 14 oz | 475 | Very stiff, almost boardy | Duffels, industrial totes, structural panels |
Porter, shots, and why two 10 oz fabrics feel different
If you have ever received two samples both described as 10 oz and found one noticeably coarser, this is why. Beyond weight, jute mills specify:
- Porter — the number of warp ends per 40 inches of width. Higher porter means more threads running lengthwise, so a finer, denser surface.
- Shots — the number of weft picks per inch. Higher shots means a tighter weave across.
A fabric can reach 10 oz by using fewer, thicker yarns or more, finer yarns. The first is cheaper and coarser, with a more open weave you can see light through; the second gives a smoother surface that takes fine print detail far better. Both are legitimately "10 oz".
Practical advice: if print quality matters, ask for the porter and shots alongside the weight, and specify them in your tech pack once you have approved a sample. If it does not matter — a plain sack, say — do not pay for a finer weave you will not see.
You should also ask about the fabric quality grade. Jute fibre is graded, and lower grades carry more visible defects: dark specks, occasional coarse "cracky" fibre and root-end material. On a natural, unbleached bag these read as character up to a point and as poor quality beyond it. Approving a physical swatch is the only reliable way to set that line.
Which weight for which bag
The right answer is the lightest fabric that survives the job, because every extra ounce costs money in fabric and again in freight.
| If the bag must… | Specify | Why |
|---|---|---|
| Be handed out at a trade fair and used a few times | 7–8 oz | Lowest unit cost. Nobody is carrying groceries in it. |
| Sit on a retail shelf and look considered | 10 oz | Holds its shape unfilled, which is what makes a bag look expensive. |
| Carry a weekly grocery shop for years | 12 oz | Handle stress and base abrasion are the failure points; weight buys margin on both. |
| Hold bottles or hampers upright | 12 oz + base board | The board does the structural work; the fabric only needs to resist tearing. |
| Protect a laptop | 12 oz + foam | Padding provides protection. Fabric provides abrasion resistance. |
| Fold into a pocket | 8 oz | Anything heavier will not fold flat or stay folded. |
| Survive being thrown around in transit | 14 oz | Duffels and industrial use. Accept that it will be stiff. |
Laminated and unlaminated
Jute is often laminated on the inside with a thin PP or PE film. This matters more than most buyers realise, and it is worth deciding deliberately rather than accepting whatever the supplier defaults to.
Lamination gives you: resistance to moisture and leaking produce, a slight stiffening that helps the bag stand up, less fibre shedding inside the bag, and a surface that resists staining.
Lamination costs you: compostability — a laminated bag cannot be composted and belongs in general waste — plus a small unit cost, a slightly plasticky interior feel, and the loss of the "no plastic at all" claim that is increasingly the reason buyers choose jute in the first place. If you intend to market the bag as plastic-free or compostable, laminate is not an option. Our guide on what you can and cannot claim goes into the detail.
A middle path that works well: unlaminated jute with a separate cotton lining. You get a clean interior and no shedding, the whole bag stays natural-fibre, and it reads as a more premium construction. It costs more than laminate.
Jute-cotton blends
Blended jute-cotton fabric, sometimes sold as jute cotton or juco, trades some of jute's stiffness and coarseness for a smoother surface and better drape. Typically used at lighter weights, around 7–9 oz.
Specify a blend when the bag needs fine print detail — small type, gradients, multi-colour registration — or when it will be handled a lot and coarse jute would feel unpleasant. Retail packaging pouches for cosmetics, tea and jewellery are the classic use. Avoid it where you need structural stiffness, because the same weight of blend is limper than pure jute.
Two expensive mistakes
Over-specifying
The instinct is that heavier equals better quality, so buyers ask for 12 oz on a bag that a well-made 10 oz would handle comfortably. The cost shows up three times: more expensive fabric, higher freight weight per piece, and poorer print definition because heavy coarse jute holds fine detail less well. On a 5,000-piece order, moving from 12 oz to 10 oz where the application allows it is a real saving with no downside your customer will notice.
Under-specifying, then blaming the supplier
The reverse is worse. A 8 oz grocery bag with rope handles and a single-stitched base will fail — usually at the handle attachment, usually within a few months — and it will fail in your customer's hand. If you asked for a price point rather than a construction, and the supplier met the price by dropping fabric weight without telling you, the fault is shared. This is exactly why the weight belongs in the quotation and in the tech pack.
How to verify what actually arrived
You do not need a laboratory to check fabric weight. Cut a precise 10 × 10 cm square from a production piece, weigh it on a jeweller's scale, and multiply the grams by 100 to get GSM. A 10 oz fabric should land near 339 g/m²; anything under about 320 is outside a normal ±5% tolerance and worth raising.
For anything contractual, use a third-party lab. A standard textile panel covering fabric weight, tensile and seam strength, colour fastness and azo dyes runs roughly USD 250–600 per style at SGS, Intertek or Bureau Veritas, and takes 7–12 working days. Do this once on the first production run of a new construction; after that, spot-check.
Also worth writing into the tech pack: the weight and the tolerance you will accept. "10 oz, ±5%" is enforceable. "10 oz" alone invites an argument about what counts as close enough.
Questions we get asked
Is burlap the same as hessian?
Yes. Burlap is the North American term, hessian the British and South Asian one, and both refer to the same woven jute fabric. Sacking is a coarser, heavier related cloth used for bulk bags.
Can I get jute in a colour at low quantity?
Not easily. Piece-dyeing has its own minimum, usually well above a few hundred bags, so a small custom-colour order pushes your MOQ up sharply. Natural jute with a printed design is the cheap route to a distinctive bag at low volume.
Does fabric weight affect shipping cost?
Yes, twice over. Heavier fabric means more kilograms per carton, and jute bags are usually volume-limited rather than weight-limited in a container — so the effect is smaller than you might expect, but it is real on air freight, where it is charged directly.
GSM conversions here are arithmetic and reliable. Prices, tolerances and mill practices are indicative — confirm with your own supplier and lab before relying on them contractually.