tare

Tare is the weight of packaging, containers, or vehicles that must be subtracted from the gross weight of a shipment to determine the net weight of the contents. In measurement and commerce, gross weight includes both the contents and the container; tare weight is the mass of the container alone; net weight is obtained by subtracting the tare from the gross.

Tare is determined by weighing the empty container on a balance or scale, or by using standard tare values for common package sizes. Modern scales often include a tare function that automatically zeros the scale to exclude the container’s weight, allowing direct measurement of the contents.

In trade and logistics, accurate tare values are essential for inventory control, pricing, and regulatory compliance. Some jurisdictions require official verification of tare values, and packaging may be marked with its tare mass or identified in shipping documents. The concept is also used in laboratory weighing, where tare masses are subtracted to measure only the sample.

Example: A bag weighs 50 g empty. When filled with product, the scale reads 300 g. The tare is 50 g, so the net contents weigh 250 g.

The term tare can have other historical or botanical uses in different contexts, but in modern practice it most often refers to the weight of packaging and containers used to determine net quantities.