Poland uses metric system, in accordance with the International System of Units (SI), whose basic units are: 1 meter (unit of length - 1 m), 1 kilogram (unit of mass - 1 kg), 1 second (unit of time - 1 s).*

Apart from the basic units there are also their derivatives, e.g. other measures of mass are 1 tonne (1 t = 1,000 kg), 1 quintal ( 1 q = 100 kg), 1 decagram (1 dag = 1/100 kg), 1 gram (1 g = 1/1000 kg), 1 miligram (1 mg = 1/1000 g), and for the length: 1 kilometer (1 km), 1 centimeter (1 cm), 1 milimeter (1 mm).

The general way to measure temperature is by using the Celsius scale (centigrade, °C).

The atmospheric pressure is measured in hectoPascals (hPa) or in torrs (milimeters of mercury) (mmHg). Speed is measured in kilometers per hour (km/h)

Below are several examples of relations between metric measurement units and measurement units in other countries, predominantly Anglo-Saxon:

Weight:
1 pound = 0.454 kg
1 (ounce) = 0.28 g

Volume:
1 pint = 0.568 l
1 UK gallon = 4.546 l
1 US gallon = 3.785 l

Length:
1 mile = 1.609 km
1 foot = 0.3 m
1 inch = 2.54 cm

Temperature
0 C = 273 K = 32 Far, 100 C= 373 K = 212 Far

*Full listing of legal measurement units in Poland is presented in the Decision of the Minister of Economy, Labour and Social Affairs of 12th May 2003 on legal measurement units, Journal of Laws No. 103 item 954, available on the website of the Central Office of Measures at: http://bip.gum.gov.pl/pl/bip/px_r_2003_103_954.pdf, and other documents presented of the COM at: http://www.gum.gov.pl/pl/site/j_miar