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We leave our glass calculator at your disposal, so that you can quickly and easily determine the weight of your glass shelves and save time by avoiding manual calculations:

Note: Glass weight is calculated in units of kilogram-force (kgf).


Although you have our glass calculator available above, in this section we explain how to manually calculate the weight of glass. This is important information to be taken into account by all professionals who work with this material in any of its variants.

The first thing you should know when calculating the weight of a glass is the value of the density of the material (we use a density of 2500 kg/m³). Based on the classic formula for calculating density, we will obtain the equation that allows the calculation of the mass of the glass shelves:

Mass (kg) = Density (kg/m³) x Volume (m³)

Now, a very common misconception is to confuse weight with mass. This confusion is made stronger by the unit of force kilopond or kilogram-force (kgf). The mass of a body is an invariable fundamental unit in any location, while the weight is the force that a body exerts and that is conditioned by its mass and the acceleration of gravity.

In our case, with the dimensions of the glass shelves (height, width and thickness) we obtain its volume. Then with the volume and density we calculate the mass in kilograms (kg).

Finally, to calculate the final weight we have two options: the traditional option in newtons (N) and the option in kilogram-force (kgf). In the case of weight in newtons, simply multiply the mass (kg) by the earth's gravity (9.81 m/s²). In this way we calculate the force exerted by the mass of the shelves:

Weight (N) = Mass (kg) x Earth Gravity (m/s²)

Talking about weight in kilogram-force is somewhat confusing, although it is unintentionally the most common. We usually say: this item weighs 70 kilos or I weigh 75 kilos. Without knowing it, we are referring to kilograms of force and not kilograms of mass. This confusion is old and part of the weight concept of the old technical system of units.

Weight (kgf) = ?

This system established that a kilogram-force (1 kgf) or kilopond was the weight exerted by a kilogram (1 kg) of mass under the effect of Earth's gravity. Just like that, without multiplying anything, without converting any unit. Therefore, the use of the shortened word kilo was normalized without referring to whether it was mass or force. Because for purposes of the old concept, the numerical value of mass and kilogram-force were the same (although one represented mass and the other force).

So having clarified the issue of weight in kilos, the correct thing is to specify and normalize the use of units in kilogram-force or in newtons. For example: a shelves with a mass of 4 kilograms (kg), has a weight of 4 kilograms of force (kgf) or 39.25 newtons (N).


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