Appendices

APPENDIX B: U.S. Metric Conversions and Energy Unit Equivalents

U.S. to Metric

Length (approximate)

1 yard (yd) = 0.9 meters (m)
1 mile (mi) = 1.6 kilometers (km)

Area (approximate)

1 square mile (sq mi, mi²) = 2.6 kilometers (km2)
1 acre = 0.4 hectares (ha) = 4,000 square meters (m2)

Mass/Weight (approximate)

1 pound (lb) = 0.45 kilograms (kg)
1 short ton = 2,000 pounds (lbs) = 0.9 metric tons (t)

Volume (approximate)

1 quart (qt) = 0.96 liters (l)
1 gallon (gal) = 3.8 liters (l)

Energy Units (approximate)

1 British thermal unit (Btu) = 250 calories = 1,055 joules
1 calorie (cal) = 4.186 joules (exactly)
1 barrel of oil = 42 U.S. gallons (gal) = 0.16 cubic meters (m3)
1 quadrillion Btu (quad) = about 170 million barrels of crude oil

Metric to U.S.

Length (approximate)

1 meter (m) = 3.3 feet (ft)
1 meter (m) = 1.1 yards (yd)
1 kilometer (km) = 0.6 miles (mi)

Area (approximate)

1 square kilometer (km²) = 0.4 square miles (sq mi, mi²)
10,000 square meters (m²) = 1 hectare (ha) = 2.5 acres

Mass/Weight (approximate)

1 gram (gm) = 0.036 ounces (oz)
1 kilogram (kg) = 2.2 pounds (lb)
1 metric ton (t) = 1,000 kilograms (kg) = 1.1 short tons

Volume (approximate)

1 liter (l) = 1.06 quarts (qt)
1 liter (l) = 0.26 gallons (gal)

Energy

1 joule = 0.24 calories (cal)
1 exajoule = 1018 joules

SOURCE: U.S. Department of Commerce, National Institute of Standards and Technology.