International System (SI) Units Definition

Physical Quantity	Name of Unit	Unit Symbol	Definition
Length	meter	m	Distance traveled by light in vacuo during 1 ⁄299, 792, 458 of a second.
Mass	kilogram	kg	Mass of the international prototype which is in the custody of the Bureau International des Poids et Mesures (BIPM) at Sèvres, near Paris.
Time	second	s	The duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium-133 atom.
Electric Current	ampere	A	The constant current which, if maintained in two parallel rectilinear conductors of infinite length, of negligible circular cross section, and placed at a distance of one meter apart in a vacuum, would produce between these conductors a force equal to 2 × 10−7 N/m length
Thermodynamic Temperature	degree Kelvin	K	The fraction 1⁄273.16 of the thermodynamic temperature of the triple point of water.
Amount of Substance	mole	mol	The amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12.
Luminous Intensity	candela	cd	Luminous intensity, in the perpendicular direction, of a surface of 1⁄600,000 square meter of a black body at the temperature of freezing platinum under a pressure of 101,325 newtons per square meter.
Force	newton	N = Kg.m/s2	That force which, when applied to a body having a mass of one kilogram, gives it an acceleration of one meter per second squared.
Work, Energy, Quantity of Heat	joule	J = N.m	The work done when the point of application of a force of one newton is displaced through a distance of one meter in the direction of the force.
Electric Charge	coloumb	C = A.s	The quantity of electricity transported in one second by a current of one ampere.
Electric Potential	volt	V = W/A	The difference of potential between two points of a conducting wire carrying a constant current of one ampere, when the power dissipated between these points is equal to one watt.
Electric Capacitance	farad	F = C/V	The capacitance of a capacitor between the plates of which there appears a difference of potential of one volt when it is charged by a quantity of electricity equal to one coulomb.
Electric Resistance	ohm	Ω = V/A	The resistance between two points of a conductor when a constant difference of potential of one volt, applied between these two points, produces in this conductor a current of one ampere, this conductor not being the source of any electromotive force.
Magnetic Flux	webber	Wb = V.s	The flux which, linking a circuit of one turn produces in it an electromotive force of one volt as it is reduced to zero at a uniform rate in one second.
Inductance	henry	H = V.s/A	The inductance of a closed circuit in which an electromotive force of one volt is produced when the electric current in the circuit varies uniformly at the rate of one ampere per second.
Luminous Flux	lumen	lm = cd.sr	The flux emitted within a unit solid angle of one steradian by a point source having a uniform intensity of one candela.
Illumination	lux	lx = lm/m2	An illumination of one lumen per square meter.

Encyclopaedia of Scientific Units, Weights and Measures: Their SI Equivalences and Origins

Decimal Equivalents of Fractions of an Inch

Fraction (Inch)	Decimal	Fraction (Inch)	Decimal	Fraction (Inch)	Decimal
1/64	0.015625	11⁄32	0.34375	43⁄64	0.671875
1/32	0.03125	23⁄64	0.359375	11⁄16	0.6875
3/64	0.046875	3⁄8	0.375	45⁄64	0.703125
1/16	0.0625	25⁄64	0.390625	23⁄32	0.71875
5/64	0.078125	13⁄32	0.40625	47⁄64	0.734375
3/32	0.09375	27⁄64	0.421875	3⁄4	0.750
7/64	0.109375	7⁄16	0.4375	49⁄64	0.765625
1/8	0.125	29⁄64	0.453125	25⁄32	0.78125
9/64	0.140625	15⁄32	0.46875	51⁄64	0.796875
5/32	0.15625	31⁄64	0.484375	13⁄16	0.8125
11/64	0.171875	1⁄2	0.500	53⁄64	0.828125
3/16	0.1875	33⁄64	0.515625	27⁄32	0.84375
13/64	0.203125	17⁄32	0.53125	55⁄64	0.859375
7/32	0.21875	35⁄64	0.546875	7⁄8	0.875
15/64	0.234375	9⁄16	0.5625	57⁄64	0.890625
1/4	0.250	37⁄64	0.578125	29⁄32	0.90625
17/64	0.265625	19⁄32	0.59375	59⁄64	0.921 875
9/32	0.28125	39⁄64	0.609375	15⁄16	0.9375
19/64	0.296875	5⁄8	0.625	61⁄64	0.953125
5/16	0.3125	41⁄64	0.640625	31⁄32	0.96875
21/64	0.328125	21⁄32	0.65625	63⁄64	0.984375

Calculated Industries 4020 Measure Master Pro Measurement Conversion Calculator

Weight and Measures

Measures of Length

1 mile = 1760 yards = 5280 feet

1 yard = 3 feet = 36 inches 1 foot = 12 inches

1 mil=0.001 inch

1 fathom = 2 yards = 6 feet 1 rod = 5.5 yards = 16.5 feet.

1 hand = 4 inches 1 span = 9 inches

1 micro-inch = one millionth inch or 0.000001 inch (1 micrometer or micron one millionth meter = 0.00003937 inch.)

Surveyor's Measure

1 mile = 8 furlongs = 80 chains

1 furlong = 10 chains = 220 yards

1 chain=4 rods = 22 yards = 66 feet = 100 links

1 link = 7.92 inches

Nautical Measure

1 league = 3 nautical miles

1 nautical mile = 6076.11549 feet = 1.1508 statute miles

1 knot = nautical unit of speed = 1 nautical mile per hour

One degree at the equator = 60 nautical miles = 69.047 statute miles 360 degrees = 21,600 nautical miles = 24,856.8 statute miles = circumference at equator

Square Measure

1 square mile = 640 acres = 6400 square chains

1 acre = 10 square chains = 4840 square yards = 43,560 square feet. An acre is equal to a square, the side of which is 208.7 feet.

1 square chain = 16 square rods = 484 square yards = 4356 square feet.

1 square rod = 30.25 square yards = 272.25 square feet = 625 square links

1 square yard = 9 square feet

1 square foot = 144 square inches

Measure used for Diameters and Areas of Electric Wires

1 circular inch = area of circle 1 inch in diameter = 0.7854 square inch

1 circular inch = 1,000,000 circular mils

1 square inch = 1.2732 circular inch = 1,273,239 circular mils

1 circular mil = the area of a circle 0.001 inch in diameter

Cubic Measure

1 cubic yard = 27 cubic feet

1 cubic foot = 1728 cubic inches

The following measures are also used for wood and masonry:

1 cord of wood = 4 × 4 × 8 feet = 128 cubic feet

1 perch of masonry = 16-1⁄2 × 1-1⁄2 × 1 foot = 24-3⁄4 cubic feet

Shipping Measure

For measuring entire internal capacity of a vessel:

1 register ton = 100 cubic feet

For measurement of cargo:

Approximately 40 cubic feet of merchandise is considered a shipping ton, unless that bulk would weigh more than 2000 pounds, in which case the freight charge may be based upon weight

40 cubic feet = 32.143 U.S. bushels = 31.16 Imperial bushels

Dry Measure

1 bushel = 1.2445 cubic feet = 2150.42 cubic inches

(U.S. or Winchester struck bushel)

1 bushel = 4 pecks = 32 quarts = 64 pints

1 peck = 8 quarts = 16 pints

1 quart=2 pints

1 heaped bushel = 11⁄4 struck bushel

1 cubic foot = 0.8036 struck bushel

1 British Imperial bushel = 8 Imperial gallons = 1.2837 cubic feet = 2218.19 cubic inches

Liquid Measure

1 U.S. gallon = 0.1337 cubic foot = 231 cubic inches = 4 quarts = 8 pints

1 quart=2 pints = 8 gills 1 pint=4 gills

1 British Imperial gallon = 1.2009

1 U.S. gallon = 277.42 cubic inches 1 cubic foot =7.48 U.S. gallons

Old Liquid Measure

1 barrel = 311⁄2 gallons 1 hogshead = 2 barrels = 63 gallons

1 pipe or butt = 2 hogsheads = 4 barrels = 126 gallons

1 tierce = 42 gallons 1 puncheon = 2 tierces = 84 gallons

1 tun=2 pipes = 3 puncheons

Apothecaries' Fluid Measure

1 U.S. fluid ounce = 8 drachms = 1.805 cubic inch = 1⁄128 U.S. gallon

1 fluid drachm = 60 minims

1 British fluid ounce = 1.732 cubic inch

Avoirdupois or Commercial Weight

1 gross or long ton = 2240 pounds 1 net or short ton = 2000 pounds

1 pound = 16 ounces = 7000 grains

1 ounce = 16 drachms = 437.5 grains

The following measures for weight are now seldom used in the United States:1 hundredweight = 4 quarters = 112 pounds (1 gross or long ton = 20 hundred-weights); 1 quarter = 28 pounds; 1 stone = 14 pounds; 1 quintal = 100 pounds

Troy Weight, used for Weighing Gold and Silver

1 pound = 12 ounces = 5760 grains

1 ounce = 20 pennyweights = 480 grains

1 pennyweight = 24 grains

1 carat =3.086 grains (used in weighing diamonds)

1 grain Troy = 1 grain avoirdupois = 1 grain apothecaries' weight

Apothecaries' Weight

1 pound = 12 ounces = 5760 grains

1 ounce = 8 drachms = 480 grains

1 drachm = 3 scruples = 60 grains

1 scruple =20 grains

Measures of Pressure

1 pound per square inch = 144 pounds per square foot = 0.068 atmosphere = 2.042 inches of mercury at 62° F. = 27.7 inches of water at 62°F = 2.31 feet of water at 62° F

1 atmosphere = 30 inches of mercury at 62° F. = 14.7 pounds per square inch = 2116.3 pounds per square foot = 33.95 feet of water at 62° F

1 foot of water at 62° F =62.355 pounds per square foot = 0.433 pound per square inch

1 inch of mercury at 62° F =1.132 foot of water = 13.58 inches of water = 0.491 pound per square inch

Miscellaneous

1 great gross = 12 gross = 144 dozen

1 quire=24 sheets

1 gross=12 dozen = 144 units

1 ream = 20 quires = 480 sheets

1 dozen=12 units

1 ream printing paper = 500 sheets

1 score=20 units

MABIS Tape Measure, Blue