35gsm vs 40gsm vs 45gsm vs 50gsm Greaseproof Paper: Which GSM Is Right for Food Packaging?

When a buyer asks us for "40gsm greaseproof paper," our next question is usually simple: what are you wrapping? A croissant, a burger with sauce, hot French fries and fried chicken can all use grease-resistant food paper, but they do not create the same demands on the sheet.

That is why choosing greaseproof paper by GSM alone often leads to either over-specifying the paper and paying for weight you do not need, or choosing a lighter grade that looks economical on paper but creates tearing, oil strike-through or converting problems later.

For many food-packaging applications, 35–40gsm is a practical starting range for light wrapping and bakery use; 40–45gsm is common when more body and handling strength are needed for burgers, sandwiches and general takeaway; and 45–50gsm may be considered for heavier handling or more demanding converting. But GSM and grease resistance are not the same specification. The final choice should also consider KIT level, food temperature, contact time, printing and the converting process.

35gsm vs 40gsm vs 45gsm vs 50gsm: Quick Buyer Comparison

 These are starting points, not universal rules. Two papers at the same GSM can behave differently because fiber structure, density, porosity, formation and surface properties are not identical from one grade to another.

What Does GSM Actually Tell You?

GSM means grams per square meter. A 35gsm sheet weighs 35 grams per square meter; a 50gsm sheet weighs 50 grams per square meter. For a buyer, that number mainly tells you how much paper mass is present in a given area.

As GSM increases, the paper will usually gain body, opacity and handling strength, while a lighter sheet will usually feel more flexible and use less material. That matters for wrapping speed, folding, bag making, sheet stiffness and material cost per pack.

What GSM does not tell you

GSM does not, by itself, tell you how long the paper will resist hot oil, whether it is suitable for direct food contact, how it will run on your printing or bag-making line, or whether it has the grease-resistance level your product needs. Those are separate performance questions.

35gsm Greaseproof Paper: Best When Flexibility and Material Efficiency Matter

35gsm greaseproof paper is often a sensible starting point for light-duty food wrapping, bakery liners, bread, dry snacks and interleaving where flexibility and low material use are more important than high handling strength.

It can also work well for printed food wrapping when the food is not excessively oily and the converting process is gentle. The risk is not that 35gsm is "too thin" in every case; the real risk is using it where the wrap is pulled, folded aggressively, exposed to hot oil for a long time or expected to carry more mechanical load than the sheet can comfortably handle.

40gsm Greaseproof Paper: The Practical All-Round Starting Point

For many buyers, 40gsm greaseproof paper is where the conversation starts. It gives more body than 35gsm while remaining flexible enough for burger wrapping paper, sandwich paper, bakery sheets, food basket liners and many general takeaway applications.

For converters, 40gsm can also provide a useful balance between material efficiency and runnability. But a 40gsm burger wrap and a 40gsm bakery liner may still require different grease-resistance levels, surface characteristics or printing specifications. The GSM can be the same while the grade is not.

45gsm Greaseproof Paper: When Handling Strength Becomes More Important

45gsm greaseproof paper is worth considering when 40gsm feels too soft, tears too easily in the real packing process, or does not give enough body for the finished wrap or liner. It is often considered for oily takeaway foods, fried-food liners, larger sheets and printed wraps where appearance and handling matter as much as grease control.

The key question is whether the extra 5gsm solves a real problem. If the issue is grease penetration rather than strength, moving to 45gsm without changing the grease-resistance specification may not fix it.

50gsm Greaseproof Paper: More Material, Not Automatically More Grease Resistance

50gsm greaseproof paper provides more paper mass and can offer a firmer, more durable feel for heavy wrapping, food bags and demanding handling. It may make sense when the package needs extra body, when sheets are large, or when the converting process puts more stress on the paper.

But 50gsm should not be treated as the "highest quality" choice by default. If a 40gsm or 45gsm grade already meets the strength and grease-resistance requirement, the additional basis weight simply adds material and cost.

GSM vs KIT Level: Do Not Use One to Replace the Other

This is one of the most common specification mistakes in grease-resistant food paper. GSM measures basis weight. KIT testing is used to compare grease repellency. TAPPI T 559 is commonly referenced for the KIT test, but the test result should still be interpreted together with the actual food application.

In practical purchasing language, "40gsm + required KIT level + application" is a much better RFQ than "40gsm greaseproof paper." It tells the supplier whether you are solving a strength problem, an oil-resistance problem, or both.

For a deeper explanation of KIT ratings, link the phrase "greaseproof paper KIT level" to the dedicated Sure Paper KIT guide rather than repeating the full KIT topic here.

Which GSM Is Best for Different Food Packaging Applications?

For Burgers and Sandwiches, Look Beyond "Burger Wrapping Paper GSM"

A burger can be relatively dry, or it can contain melted cheese, mayonnaise, sauce and a high-fat patty. The paper may be wrapped for five minutes at a counter or stay in a delivery bag much longer. That is why two burger brands can need different specifications even if both ask for 40gsm food wrapping paper.

For this application, the useful buying questions are: how oily is the product, how long will it stay wrapped, is the paper printed, how tightly is it folded, and does the outer carton or bag need protection from grease marks?

For Fried Food, Contact Time Can Matter as Much as GSM

French fries, fried chicken and other hot foods can expose the paper to surface oil, heat and pressure at the same time. A thicker sheet may give better handling strength, but grease performance still needs to be validated separately. If the food is held for delivery rather than served immediately, contact time becomes even more important.

For buyers searching "greaseproof paper for fried food," the safest approach is to treat GSM as the handling specification and KIT/application testing as the grease-performance specification.

Printing and Converting: The Specification Buyers Often Add Too Late

A paper can look good in a hand sample and still create problems on a real production line. If you are printing, slitting, bag making, folding or running automatic wrapping equipment, the converting process should be part of the paper selection from the start.

Lower GSM can improve flexibility and reduce material use, but the sheet may be more sensitive to web breaks, edge damage or tearing. Higher GSM can improve body and strength, but may change folding behaviour, glue response and machine settings. For printed greaseproof paper, surface consistency and printability also matter.

Greaseproof Paper Roll or Sheet: Which Format Should You Buy?

Why the Lowest GSM Is Not Always the Lowest Cost

For the same sheet area, moving from 40gsm to 50gsm increases paper mass by 25%. That difference matters when a converter or foodservice group is buying millions of sheets. So it is reasonable to test whether a lighter grade can reduce material use.

But the saving only exists if the lighter paper still runs reliably. If 35gsm causes more tearing, machine stops, rejected printing or wrapping waste than 40gsm, the lower paper price can become a higher total packaging cost. The better target is not "lowest GSM." It is the lowest GSM that performs reliably in the real application.

A Better Way to Request a Greaseproof Paper Quote

A complete RFQ helps the supplier recommend the right grade faster and makes quotations easier to compare. It also reduces the risk of receiving three prices for three technically different papers that all happen to be called "40gsm greaseproof paper."

Common Buying Mistakes We Would Avoid

• Choosing 50gsm simply because it sounds stronger, without checking whether 40gsm already works.
• Increasing GSM to solve grease strike-through when the real issue is the required grease-resistance level.
• Comparing supplier prices without confirming whether the KIT level, roll specifications and food-contact requirements are the same.
• Approving a hand sample but skipping the printing or converting trial for high-volume production.
• Using "greaseproof paper," "wax paper" and "silicone parchment paper" as if they were interchangeable products.

If the application involves high-temperature baking or a strong non-stick requirement, silicone-coated baking parchment may be more appropriate than standard greaseproof wrapping paper. Use an internal link to the Sure Paper baking paper page where that distinction helps the reader.

Frequently Asked Questions About Greaseproof Paper GSM

What is the best GSM for burger wrapping paper?

40gsm and 45gsm are practical starting points for many burger and sandwich applications. The final choice depends on sauce and oil exposure, contact time, wrapping pressure, required KIT level and whether the paper must be printed or converted.

Is 50gsm greaseproof paper more grease-resistant than 40gsm?

Not automatically. 50gsm contains more paper mass and may offer more body and mechanical strength, but grease resistance is a separate property. Compare the grease-resistance specification and actual application performance.

What GSM greaseproof paper is suitable for French fries?

40–50gsm may be considered depending on the liner format, holding time and handling requirement. For hot fried food, confirm grease resistance and contact conditions rather than choosing by GSM alone.

Can 35gsm greaseproof paper be used for food packaging?

Yes. 35gsm can be suitable for lightweight food wrapping, bakery liners, bread, dry snacks and lower-grease applications when the required strength and grease resistance are met.

Does a higher KIT level mean I should also buy a higher GSM?

No. KIT level and GSM measure different things. A buyer can require a higher grease-resistance level without automatically moving to a heavier basis weight.

What should I specify when buying greaseproof paper rolls?

In addition to GSM and grease resistance, provide roll width, core diameter, maximum roll diameter, winding direction, printing or converting method and expected order volume.

Is greaseproof paper the same as parchment paper?

No. Standard greaseproof paper is mainly selected for oil and grease resistance in wrapping and foodservice. Silicone-coated parchment paper is normally chosen when higher heat resistance and non-stick performance are required for baking.

Choose the GSM Around the Application, Not the Other Way Around

There is no universal "best" greaseproof paper GSM. 35gsm can be efficient and flexible; 40gsm is a strong all-round starting point; 45gsm adds body when handling becomes more demanding; and 50gsm can provide extra durability where the application genuinely needs it.

The better purchasing sequence is: application first, then grease exposure and contact time, then grease-resistance requirement, then GSM, format and converting details. That approach gives you a specification that is easier to test, compare and scale.

If you are sourcing greaseproof paper for burgers, fried food, bakery, tray liners or printed food wrapping, send Sure Paper your application, target GSM, required KIT level, size or roll specifications, printing/converting method, estimated volume and destination. We can help narrow the options for sample or trial evaluation before a larger order.