{"name":"Common exact unit conversion factors","version":"2026-09-13","method":"Multiply a value in the source unit by factor to obtain the listed SI base unit.","scope":["length","area","volume"],"limitations":["US liquid gallon is not the imperial gallon.","Area and volume factors reflect squared or cubed length definitions.","Display rounding should not replace the published factor in calculations."],"rows":[{"category":"Length","from":"inch","symbol":"in","baseUnit":"metre","baseSymbol":"m","factor":0.0254,"definition":"1 in = 0.0254 m exactly"},{"category":"Length","from":"foot","symbol":"ft","baseUnit":"metre","baseSymbol":"m","factor":0.3048,"definition":"1 ft = 0.3048 m exactly"},{"category":"Length","from":"yard","symbol":"yd","baseUnit":"metre","baseSymbol":"m","factor":0.9144,"definition":"1 yd = 0.9144 m exactly"},{"category":"Length","from":"mile","symbol":"mi","baseUnit":"metre","baseSymbol":"m","factor":1609.344,"definition":"1 mi = 1609.344 m exactly"},{"category":"Length","from":"centimetre","symbol":"cm","baseUnit":"metre","baseSymbol":"m","factor":0.01,"definition":"1 cm = 0.01 m exactly"},{"category":"Area","from":"square foot","symbol":"ft²","baseUnit":"square metre","baseSymbol":"m²","factor":0.09290304,"definition":"1 ft² = 0.09290304 m² exactly"},{"category":"Area","from":"square yard","symbol":"yd²","baseUnit":"square metre","baseSymbol":"m²","factor":0.83612736,"definition":"1 yd² = 0.83612736 m² exactly"},{"category":"Area","from":"acre","symbol":"acre","baseUnit":"square metre","baseSymbol":"m²","factor":4046.8564224,"definition":"1 acre = 4046.8564224 m² exactly"},{"category":"Area","from":"hectare","symbol":"ha","baseUnit":"square metre","baseSymbol":"m²","factor":10000,"definition":"1 ha = 10000 m² exactly"},{"category":"Volume","from":"cubic foot","symbol":"ft³","baseUnit":"cubic metre","baseSymbol":"m³","factor":0.028316846592,"definition":"1 ft³ = 0.028316846592 m³ exactly"},{"category":"Volume","from":"cubic yard","symbol":"yd³","baseUnit":"cubic metre","baseSymbol":"m³","factor":0.764554857984,"definition":"1 yd³ = 0.764554857984 m³ exactly"},{"category":"Volume","from":"US liquid gallon","symbol":"US gal","baseUnit":"cubic metre","baseSymbol":"m³","factor":0.003785411784,"definition":"1 US gal = 0.003785411784 m³ exactly"}]}