GSM is the unit used to measure the weight of paper or textiles. It is a key indicator to judge the thickness, density and strength of paper, an important standard to judge the thickness and quality of paper in the paper industry, and an important indicator to evaluate the type of paper and choose the appropriate use. Widely used in printing, packaging, publishing and other fields. In the paper industry, the larger the GSM value, the thicker the paper is usually, heavier, stronger, more durable, suitable for high-end printing and long-term storage; the smaller the value, the thinner the paper, suitable for disposable or mass printing.

 Tables of Content

What Does GSM Stand for in Paper?
Difference Between Paper Weight and Thickness
The effect of GSM on paper quality
Environmental protection considerations
Common questions about the GSM

Explanation of the Acronym GSM (Grams per Square Meter)

GSM in paper stands for’’Grams per Square Mete’’, a unit that measures the weight of paper. It indicates the weight of one square meter of paper (measured in grams) and is used to reflect the paper’s thickness and density.

Historical Context and Development of GSM as a Measurement Standard

The history of GSM (Grams per Square Meter) as a paper measurement standard dates back to the early days of standardization in the paper and printing industry.

Traditionally, different regions and countries used various methods to measure paper weight. For example, the United States and the United Kingdom commonly used’’pound’’ (lb) to indicate paper weight, while Europe and most international markets adopted the more straightforward and standardized GSM system.

GSM gained widespread acceptance because it directly reflects the weight of paper per square meter, eliminating the need to account for paper size, thickness, or pressing techniques. This makes it a more accurate and universal method for comparing different types of paper.

Importance of GSM in the paper industry

-GSM is a key indicator for determining the thickness, density, and strength of paper.

-Different GSM levels affect a paper’s ink absorption, color performance, and print clarity. For example, thicker paper with a higher GSM is better suited for high-quality image and text printing, while thinner paper with a lower GSM is ideal for standard documents or bulk promotional materials.

-Various printed materials, packaging solutions, or publications require different levels of strength and texture. Choosing the right GSM helps enhance the product’s professionalism and quality.

-Environmental and sustainability considerations: Lower GSM paper can help reduce paper consumption, making it a more eco-friendly choice in some cases. When selecting recycled or sustainably sourced paper, GSM is also an important factor to consider.

Definition of Paper Weight and Its Measurement

Paper weight refers to the mass of one square meter of paper, commonly measured in GSM (Grams per Square Meter). This value indicates the actual weight of one square meter of the paper (measured in grams).

Measurement Method:

In standard conditions, paper weight can be identified directly by checking the indicated GSM value — there’s no need to cut or weigh the paper. For example, 80 GSM paper weighs 80 grams per square meter, and this value remains consistent regardless of the paper’s size or cut.

Definition of Paper Thickness and Its Difference from Weight

Paper thickness refers to the actual physical thickness of the paper, typically measured in microns (µm) or millimeters (mm) to indicate how thick the paper is.

Key Differences:

-Paper weight (GSM) and thickness are not always proportional.

-Different paper materials (such as coated paper, kraft paper, etc.) can have different thicknesses even with the same GSM. For example:

-Loosely structured paper may feel thicker but weigh less.

-Densely packed paper may feel thinner but weigh more.

Relationship Between GSM, Weight, and Thickness

-GSM (weight) and thickness are generally correlated — higher GSM paper is usually thicker. However, factors like paper material and pressing techniques can influence thickness.

-Weight is better for assessing paper density and overall feel, while thickness directly affects the paper’s texture, stacking ability, and folding performance.

-When selecting paper, GSM is useful for evaluating paper quality and intended use, while thickness is more relevant for determining the product’s volume, stacking efficiency, and fold durability.

Effect of GSM on robustness and strength:

The higher the GSM, the thicker the paper is and more robust and durable.

Low GSM paper (60-90 GSM): thin and light, easy to fold and bend, but not tear resistant, suitable for leaflets, disposable or short-term use prints such as notebooks.

Medium GSM paper (100-150 GSM): with a certain thickness and strength, suitable for brochures, posters and other products that need moderate durability and hand feel.

High GSM paper (200 + GSM): thick and strong, strong folding resistance, suitable for business cards, greeting cards, packaging boxes and other products that need stiffness and wear resistance.

The higher the paper GSM, the less likely it is to break or deform, so the paper with a higher GSM should be selected for greater durability.‍

Effect of GSM on printing effects and surfaces

GSM:It not only affects the thickness and hand feel of the paper, but also is directly related to the printing effect:

Low GSM paper due to the fiber is loose, easy to infiltrate ink, resulting in the text is not clear enough. Suitable for black and white text, concise design does not pursue the pursuit of fine image printing.

The paper surface of higher GSM paper is more smooth, higher density, uniform ink absorption, better color performance, and is suitable for high-definition text, fine printing and bronzing, UV and other special processes.

Paper with special surface treatment (such as coated paper, dumb powder paper): regardless of the GSM level, the surface is relatively smooth, which can significantly improve the printing effect.

Choosing paper suitable for GSM helps to ensure full color, sharp graphics, avoid print wrinkles, ink and other problems.

Consideration when selecting the right GSM for specific purposes and the common GSM ranges and their uses

When selecting a paper GSM, combine the following factors:

-Flyers and Leaflets: Choose 60-100 GSM for easy folding and mass distribution.

-Brochures and Posters: Opt for 100-170 GSM to achieve a balance between texture and ease of flipping or displaying.

-Business Cards and Packaging Boxes: Select paper with 200 GSM or higher to ensure stiffness, durability, and a premium feel.

Printing Techniques:

-For special printing techniques such as foil stamping, embossing, or UV coating, it is recommended to use paper with a higher GSM to prevent deformation or damage.

Usage Scenarios:

-For indoor short-term promotional materials, lower GSM paper can be used.

-For outdoor long-term advertisements or posters, higher GSM paper is recommended to enhance durability and resistance to wear and tear.

Choosing the right GSM not only improves the paper’s texture and visual appeal but also effectively controls costs while meeting various application needs.

Paper Selection and Testing Recommendations:

Before finalizing your paper choice, consider the following steps:

-Request Samples: Ask suppliers for paper samples with different GSM values to personally evaluate their thickness, texture, and print quality.

-Printing Test: Conduct print tests on samples to check for color vibrancy, text clarity, and image sharpness, ensuring the paper’s surface smoothness and ink absorption meet expectations.

-Folding and Cutting Test: Particularly for packaging boxes or folded brochures, test the paper’s crease quality, tear resistance, and edge finishing.

-Environmental Test: If the paper will be used outdoors, test its moisture resistance, UV resistance, and overall durability in varying conditions.

By carefully considering project requirements, printing techniques, and budget — along with thorough sample testing — you can confidently select the most suitable GSM to ensure a perfect balance between quality and cost.

Discussion of sustainable paper options and GSM:

1. Recycled Paper:The recycled paper is made of recycled fibers, reducing the felling of the original trees during the production process.

2. FSC Certified Paper (Forest Stewardship Council)

FSC certification ensures that paper originates from responsibly managed forests, maintaining ecosystems and biodiversity. The GSM of this paper is rich to meet a variety of needs from light propaganda to thick packaging boxes.

Impact of GSM on recyclability and environmental impacts

1 Paper with lower GSM has a relatively small carbon footprint due to less material use and less energy and raw materials consumed during production. But the thinner paper is easy to damage, which may lead to reduced use efficiency.

2. Paper with higher GSM is more durable and suitable for reuse or long-term preserved prints, reducing the waste of resources. However, due to the heavier materials, the energy consumption in the production and transportation process is relatively large.

3. The particularity of coated paper: some high GSM paper is treated with overlighting and film mulching, which improves the visual effect and hand feel, but may reduce its recyclability. Therefore, environmental protection and beauty should be balanced in the design and material selection.

Eco-friendly paper production trend:

1. Lightweight paper (Lightweight Paper): By improving the production process, ensuring the strength and printing effect, while reducing GSM to reduce raw material consumption and transportation energy consumption.

1. Non-plastic or environmentally friendly coating paper: the traditional mulching process is bad for paper recycling, and the new environmental protection coating (such as water-based coating) to replace plastic mulching, improve the environmental protection and recyclability of paper.

3. Utilization of renewable fiber: More and more enterprises use non-wood fiber such as bamboo pulp, sugarcane bagasse and cotton to reduce their dependence on forest resources.

A. Common misconceptions about GSM:

Myth # 1: The higher the GSM, the better the paper quality

Truth: The GSM only represents the weight of the paper, and is not directly equivalent to the mass. Paper quality is also affected by the fiber material, surface treatment, production process and other factors. For example, coated paper with low GSM may be more shiny and smoother than regular paper with high GSM.

Myth # 2: GSM and thickness are the same concept

Truth: The GSM represents the weight of the paper, while the thickness is the physical thickness of the paper. Although the two are related, the thickness of different paper materials may be obviously different under the same GSM.

Myth # 3: The paper with a lower GSM is easy to break, and the higher paper must be stronger

Truth: While paper with higher GSM is usually more durable, the durability is also related to the fibrous structure and coating process. For example, high-quality 80 GSM paper may be stronger than low-quality 100 GSM paper.

Myth # 4: Just focus on GSM without considering other factors

Truth: In addition to GSM, paper stiffness, ink absorption, gloss and environmental properties should also be considered to ensure that it meets specific project needs.

B. FAQs for GSM and paper selection:

-Q: How to judge the applicable scenarios of different GSM paper?

A: Generally speaking: 60-90 GSM: suitable for printing paper, leaflets, notebook inside pages, etc.

100-150 GSM: suitable for brochures, magazine inside pages, folding, etc.

200 GSM and above: suitable for business cards, invitation letters, packaging boxes and other need high support products.

-Q: Why does the same GSM paper have different feel and thickness?

A: This is because the paper material, pressing process and density are different. For example, coated paper is tight, delicate and thin, while rice paper or kraft paper fiber is loose and feels thicker.

-Q: How to balance cost and quality when choosing a GSM?

A: It is recommended to choose a "just right" GSM according to the project requirements. For example, disposable products such as leaflets can choose lower GSM to save cost; while high-end business cards and packaging boxes emphasize texture and durability, higher GSM should be selected.

Q: How to test the actual performance of the paper?

A: Before selecting the paper, the following tests can be performed:

-Printing test: check the ink absorption and color reduction of the paper.

-Fding test: ensure that the paper is not prone to break or crack when folding.

-Durability test: Check the paper for tear resistance and water resistance (if required).

C. Further understanding of the GSM resources:

If you wish to further study GSM and paper selection, the following resources are for reference:

Industry standard literature: such as ISO 536 standard (quantitative determination of paper and cardboard), providing detailed specifications on GSM measurement.

Printing and packaging industry websites: such as FSEA (Foil Printing and Special Technology Association), PrintWeek, etc., to share the industry trends about paper, printing and packaging.

Paper Supplier and manufacturer Information: Many paper suppliers provide detailed paper specifications and application guidelines to help users understand the characteristics of different GSM papers.

Environmental certification bodies: such as FSC (Forest Regulatory Council) and PEFC (Forest Accreditation Program), can query the relevant information about sustainable paper.

Combining these resources, you can more scientifically choose the paper suitable for your project to ensure that the finished product meets both demand and environmental and budget requirements.

Conclusion

GSM (gram weight per square meter) is an important standard to measure the weight and density of paper, which directly affects the durability, printing effect and application scenarios of paper. Understanding the relationship between GSM and paper thickness and quality helps to choose paper more meets the project needs. Lightweight paper is suitable for leaflets and brochures, medium weight paper is often used for stationery and business cards, while heavy paper is suitable for posters, packaging and art prints. When purchasing paper, the project use, printing process and cost should be considered to ensure that the GSM matches the expected finished product. In addition, with the improvement of environmental awareness, the choice of recycled paper, FSC certified paper and other sustainable materials has become an industry trend. Master these key points, can be more scientific, environmental protection to choose the right paper, to bring better finished product effect for the project.