5 Key Parameters When Ordering Paper Mailing Bags

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5 Key Parameters When Ordering Paper Mailing Bags

Apr. 24, 2022

When choosing paper for your paper bags, there are many parameters to choose from and if chosen correctly, you will get the best bag and fit for your pocket.


In this case study, OnlyMailer Packaging mentions the key considerations detailed below. The parameters to choose from are GSM, BF, COBB value, MG or MF, paper brightness, etc.



The most misrepresented is GSM or grams per square meter, GSM is simply the gram weight of 1 square meter of paper. GSM is often considered a measure of strength, where an unaccomplished heavyweight boxer may still outlive the featherweight champion, but the boxer with a higher burst factor in his class will win! Paper used for paper bags is typically 35 GSM - 150 GSM. It is important to note that handworked paper bag manufacturers may push 120+ gsm products due to the fact that it is easier to die cut thicker paper, but there is hardly any capacity that cannot be handled with high BF paper that can reach 100 gsm or less.

Paper Bag

Paper Bag

Bursting Factor

Bursting factor is one of the measures of paper strength. It indicates the amount of pressure that will be applied when the paper bursts. It is a good way to know not only how much weight the bag can carry, but also how much weight the paper bag will burst under. The bursting factor of paper used in paper bags is typically 14-40 BF, and in most cases anything above 30 BF is too much.


COBB Value

COBB value is the percentage increase in weight of the paper after it is immersed in water. the lower the COBB value, the less water it will absorb and the higher the integrity of the paper when wet. This is usually an overlooked parameter in most purchase orders, but it is an important parameter in humid countries like India. Wet strength is another important parameter to look for when paper is used wet.

Paper Mailer With Handle

Paper Mailer With Handle

Wet strength is a measure of the change in the strength of the paper when wet relative to its strength when dry. Paper manufacturers may add certain chemicals and raw materials to reduce the COBB value and increase the wet strength of the paper without a significant difference in price. 20 and below COBB value and 20 and above wet strength are suitable for paper bags used to package cold products that may attract condensation and moisture or slightly wet items such as fruits and vegetables.



MG is Machine Glazed and MF is Machine Finished, the same paper that has an additional process called varnishing or calendering. Calendering is a simple process in which the paper is passed through rolls that smooth one side of the paper and give it a smooth look and feel. Because single-sided varnished paper is smooth on a microscopic level, it has less variation in grammage, less variation in strength, etc., and very high print quality because the ink gets a smoother base. machine Finished is a simple paper finish that is rough on both sides. The other qualities of the paper are the same as GSM, BF, etc., but also more expensive than MF MG paper glows at its top, while MF does not.

Online Paper Mailer With Gusset

Online Paper Mailer With Gusset

Paper Brightness

The brightness of the paper comes into play when we use various white papers. Bleached Kraft or MG posters are common varieties of white paper used for paper bags. The brightness of the paper refers to how much light the paper reflects. Not only is this parameter important when sourcing printed materials, but the look and feel of non-printed white paper can change dramatically when brightness drops.


Unless defined and locked in a purchase order, suppliers may pull old bait and switch to customers because without this parameter, it is difficult to lock in the look and feel of the paper because color and shading are independent of brightness. This becomes the most important overlooked feature due to the healthy cost difference between low and high brightness papers.

Natural-Shade paper is approx. 5%-10% cheaper than dyed paper. Those who are not looking to print may choose to order natural shade, which is grayish brown, other properties except brightness may remain same in natural shade.

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Focusing on long-term development, OnlyMailer Packaging specializes in the production of paper mailing bag and use environmentally friendly materials which are sustainable , recyclable, degradable, high strength, waterproof. It is an ideal substitute for traditional plastic courier bag.


We firmly believe that quality and continuous innovation are fundamental to the survival and development of an enterprise. All of our products are customized according to customer requirements, welcome to send your inquire.

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