Weight levels - and what it actually means

Quick facts

General Overview:

Weight (Grammage) is calculated as the mass of the product per unit of area (g/m2). This is also known as paper density or basis weight and usually is given to represent the thickness of the paper. There are two systems of measurement - the UK measures this as grams per square metre - which is the weight in grams of a 1 metre x 1 metre sheet. This means if a sheet of 1m x 1m weighs 90 grams then the paper weight is given as 90g/m2. The higher the number the heavier (and usually thicker) the paper.

The second method of measurement employed (in N. America) uses the US Paper Density System. With this system different paper types are split into grades such as Cover paper, tissue paper, bond/writing paper, newsprint grade etc.  Each grade of paper has a standard size and number of sheets e.g. 'Text' paper which is lightweight will be calculated on the basis of 500 sheets 25" x 38" in size, while 'Bond' paper which is stronger and more rigid is calculated using 500 sheets at 17" x 22".  

Due to the way papers are manufactured, i.e. some are coated or uncoated, some media has been compressed during the manufacturing process, some the fibres are not made as compactly. In this way it is possible for paper to have the same weight but have a physical variance in thickness.  

35gsm to 55gsm: This is very thin paper - most newspaper will commonly be printed on this paper thickness

75gsm to 80gsm: Average copier or printer paper 

90gsm to 100gsm:  Good weight printing paper - a step up from the average 80gsm weight paper of many large format paper rolls and tends to be in the next price bracket. Generally a little bit thicker and more opaque (harder to see through) than standard copy paper

120gsm to 140gsm:  Often used for posters and flyers and business leaflets - sturdy enough to withstand a little bit of wear and tear

210gsm to 300gsm:  This is approaching card but will still have a bit of a bend when held with two fingers - often used for magazine covers or high quality promotional flyers

350gsm to 400gsm:  Essentially this will stand up under its own weight and is essentially card - often used for business cards, wedding invitations, birthday cards 

Test Methods include:

ISO 536 - quantifies the basis weight of paper under conditioned circumstances and includes the sum of fibrious materials, fillers, process materials and water

ASTM D646 - quantifies the standard test method for mass per unit area of paper and paperboard of Aramid Papers (Basis Weight)

Tappi T 410 - quantifies the ratio that is the basis for the cost of paper and paperboard. It also determines the values of many physical properties such as bursting strength, thickness and bulk and the calculation of many strength properties.

Examples of HP Paper weights:

HP Universal Bond Paper - 80 g/m2
HP Bright White Inkjet Bond paper - 90 g/m2
HP Coated paper - 90 g/m2
HP Everyday Matte Polypropylene - 120 g/m2
HP Heavyweight Coated paper - 131 g/m2
HP Durable Banner with DuPont Tyvek - 140 g/m2
HP Super Heavyweight plus matte paper - 210 g/m2
HP Collector Satin Canvas - 400 g/m2
HP Professional Matte Canvas - 430 g/m2
HP Universal Matte Canvas - 350 g/m2