The following table lists the metric base units of measurement and their symbols:
Measurement Metric Base Unit length meter (m) mass gram (g) time second (s) current ampere (A) thermodynamic temperature kelvin (K) amount of substance mole (mol) luminous intensity candela (cd) plane angle radian (rad) solid angle steradian (sr)
Note that the metric symbols, or abbreviations, are neither italicized nor capitalized (except ampere (A) and kelvin (K) which are derived from proper names). The symbols are not followed by a period and do not change in plural form.
The metric symbol is used only when it follows a number; otherwise, it is spelled out:
The 1500 m race, slightly under 1 mile in length, is one of the most exciting events in track and field.
International track meets use meters instead of yards as the standard unit of distance measure.
What do the metric prefixes (kilo, mega, giga, milli, etc.) mean?
All derived units in the metric system are in multiples of ten. The prefixes in the table below, in combination with the basic unit names, provide the multiples in the system, e.g., the unit meter with the prefix kilo- produces kilometer, meaning "1,000 meters."
Prefix Symbol Multiple deka- da 10 hecto- h 102 kilo- k 103 mega- M 106 giga- G 109 tera- T 1012 deci- d 10-1
Prefix Symbol Multiple centi- c 10-2 milli- m 10-3 micro- µ 10-6 nano- n 10-9 pico- p 10-12 femto- f 10-15 atto- a 10-18
Metric Measures and Common Equivalents
Metric Common Measure Equivalent Kilometer 0.62137 mile Meter 39.37 inches Centimeter 0.3937 inch Millimeter 0.0394 inch Hectare 2.471 acres Are 119.6 sq yards Centiare 1,550 sq inches
Metric Common Measure Equivalent Liter 1.057 quarts Milliliter 0.034 fluid ounce Kilogram 2.2046 pound, avdp Kilogram 2.6795 pound, troy Gram 0.0353 ounce, avdp Gram 0.03215 ounce, troy Milligram 0.01543 grain, avdp
Common Measures and Metric Equivalents
Common Metric Measure Equivalent Inch 2.54 centimeters Foot 0.3048 meter Yard 0.9144 meter Rod 5.029 meters Mile 1.6093 kilometers Sq inch 6.452 sq centimeters Sq foot 0.0929 sq meter Sq yard 0.836 sq meter Sq rod 25.29 sq meters Acre 0.4047 hectare Sq mile 259 hectares Cu inch 16.39 cu centimeters Cu foot 0.0283 cu meter Cu yard 0.7646 cu meter Cord 3.625 steres
Common Metric Measure Equivalent Liquid quart (US) 0.9463 liter Dry quart (US) 1.101 liters Quart, imperial 1.136 liters Gallon (US) 3.785 liters Gallon, imperial 4.546 liters Peck (US) 8.810 liters Peck, imperial 9.092 liters Bushel (US) 35.24 liters Bushel, imperial 36.37 liters Dram, avdp 1.772 grams Ounce, avdp 28.35 grams Pound, avdp 0.4536 kg Grain 0.0648 gram Ounce, troy 31.103 grams Pound, troy 0.3732 kg