The Central Intelligence Agency (CIA) is an independent US
Government agency responsible for providing national security
intelligence to senior US policymakers.
Note: At this time, only three countries - Burma,
Liberia, and the US - have not adopted the International System of Units
(SI, or metric system) as their official system of weights and measures.
Although use of the metric system has been sanctioned by law in the US
since 1866, it has been slow in displacing the American adaptation of the
British Imperial System known as the US Customary System. The US is the
only industrialized nation that does not mainly use the metric system in
its commercial and standards activities, but there is increasing acceptance
in science, medicine, government, and many sectors of industry.
Mathematical Notation
Mathematical Power
Name
1018 or 1,000,000,000,000,000,000
one quintillion
1015 or 1,000,000,000,000,000
one quadrillion
1012 or 1,000,000,000,000
one trillion
109 or 1,000,000,000
one billion
106 or 1,000,000
one million
103 or 1,000
one thousand
102 or 100
one hundred
101 or 10
ten
100 or 1
one
10-1 or 0.1
one-tenth
10-2 or 0.01
one-hundredth
10-3 or 0.001
one-thousandth
10-6 or 0.000 001
one-millionth
10-9 or 0.000 000 001
one-billionth
10-12 or 0.000 000 000 001
one-trillionth
10-15 or 0.000 000 000 000 001
one-quadrillionth
10-18 or 0.000 000 000 000 000 001
one-quintillionth
Metric
Interrelationships
Prefix
Symbol
Length, weight, or capacity
yotta
Y
1024
zetta
Z
1021
exa
E
1018
peta
P
1015
tera
T
1012
giga
G
109
mega
M
106
kilo
k
103
hecto
h
102
deka
da
101
basic unit
-
1 meter, 1 gram, 1 liter
deci
d
10-1
centi
c
10-2
milli
m
10
-3
micro
u
10-6
nano
n
10-9
pico
p
10-12
femto
f
10-15
atto
a
10-18
zepto
z
10-21
yocto
y
10-24
CONVERSION
FACTORS
To Convert From
To
Multiply By
acres
ares
40.468 564 224
acres
hectares
0.404 685 642 24
acres
square feet
43,560
acres
square kilometers
0.004 046 856 422 4
acres
square meters
4,046.856 422 4
acres
square miles (statute)
0.001 562 50
acres
square yards
4,840
ares
square meters
100
ares
square yards
119.599
barrels, US beer
gallons
31
barrels, US beer
liters
117.347 77
barrels, US petroleum
gallons (British)
34.97
barrels, US petroleum
gallons (US)
42
barrels, US petroleum
liters
158.987 29
barrels, US proof spirits
gallons
40
barrels, US proof spirits
liters
151.416 47
bushels (US)
bushels (British)
0.968 9
bushels (US)
cubic feet
1.244 456
bushels (US)
cubic inches
2,150.42
bushels (US)
cubic meters
0.035 239 07
bushels (US)
cubic yards
0.046 090 96
bushels (US)
dekaliters
3.523 907
bushels (US)
dry pints
64
bushels (US)
dry quarts
32
bushels (US)
liters
35.239 070 17
bushels (US)
pecks
4
cables
fathoms
120
cables
meters
219.456
cables
yards
240
carat
milligrams
200
centimeters
feet
0.032 808 40
centimeters
inches
0.393 700 8
centimeters
meters
0.01
centimeters
yards
0.010 936 13
centimeters, cubic
cubic inches
0.061 023 744
centimeters, square
square feet
0.001 076 39
centimeters, square
square inches
0.155 000 31
centimeters, square
square meters
0.000 1
centimeters, square
square yards
0.000 119 599
chains, square surveyor's
ares
4.046 86
chains, square surveyor's
square feet
4,356
chains, surveyor's
feet
66
chains, surveyor's
meters
20.116 8
chains, surveyor's
rods
4
cords of wood
cubic feet
128
cords of wood
cubic meters
3.624 556
cords of wood
cubic yards
4.740 7
cups
liquid ounces (US)
8
cups
liters
0.236 588 2
degrees Celsius
degrees Fahrenheit
multiply by 1.8 and add 32
degrees Fahrenheit
degrees Celsius
subtract 32 and divide by 1.8
dekaliters
bushels
0.283 775 9
dekaliters
cubic feet
0.353 146 7
dekaliters
cubic inches
610.237 4
dekaliters
dry pints
18.161 66
dekaliters
dry quarts
9.080 829 8
dekaliters
liters
10
dekaliters
pecks
1.135 104
drams, avoirdupois
avoirdupois ounces
0.062 55
drams, avoirdupois
grains
27.344
drams, avoirdupois
grams
1.771 845 2
drams, troy
grains
60
drams, troy
grams
3.887 934 6
drams, troy
scruples
3
drams, troy
troy ounces
0.125
drams, liquid (US)
cubic inches
0.226
drams, liquid (US)
liquid drams (British)
1.041
drams, liquid (US)
liquid ounces
0.125
drams, liquid (US)
milliliters
3.696 69
drams, liquid (US)
minims
60
fathoms
feet
6
fathoms
meters
1.828 8
feet
centimeters
30.48
feet
inches
12
feet
kilometers
0.000 304 8
feet
meters
0.304 8
feet
statute miles
0.000 189 39
feet
yards
0.333 333 3
feet, cubic
bushels
0.803 563 95
feet, cubic
cubic decimeters
28.316 847
feet, cubic
cubic inches
1,728
feet, cubic
cubic meters
0.028 316 846 592
feet, cubic
cubic yards
0.037 037 04
feet, cubic
dry pints
51.428 09
feet, cubic
dry quarts
25.714 05
feet, cubic
gallons
7.480 519
feet, cubic
gills
239.376 6
feet, cubic
liquid ounces
957.506 5
feet, cubic
liquid pints
59.844 16
feet, cubic
liquid quarts
29.922 08
feet, cubic
liters
28.316 846 592
feet, cubic
pecks
3.214 256
feet, square
acres
0.000 022 956 8
feet, square
square centimeters
929.030 4
feet, square
square decimeters
9.290 304
feet, square
square inches
144
feet, square
square meters
0.092 903 04
feet, square
square yards
0.111 111 1
furlongs
feet
660
furlongs
inches
7,920
furlongs
meters
201.168
furlongs
statute miles
0.125
furlongs
yards
220
gallons, liquid (US)
cubic feet
0.133 680 6
gallons, liquid (US)
cubic inches
231
gallons, liquid (US)
cubic meters
0.003 785 411 784
gallons, liquid (US)
cubic yards
0.004 951 13
gallons, liquid (US)
gills (US)
32
gallons, liquid (US)
liquid gallons (British)
0.832 67
gallons, liquid (US)
liquid ounces
128
gallons, liquid (US)
liquid pints
8
gallons, liquid (US)
liquid quarts
4
gallons, liquid (US)
liters
3.785 411 784
gallons, liquid (US)
milliliters
3,785.411 784
gallons, liquid (US)
minims
61,440
gills (US)
centiliters
11.829 4
gills (US)
cubic feet
0.004 177 517
gills (US)
cubic inches
7.218 75
gills (US)
gallons
0.031 25
gills (US)
gills (British)
0.832 67
gills (US)
liquid ounces
4
gills (US)
liquid pints
0.25
gills (US)
liquid quarts
0.125
gills (US)
liters
0.118 294 118 25
gills (US)
milliliters
118.294 118 25
gills (US)
minims
1,920
grains
avoirdupois drams
0.036 571 43
grains
avoirdupois ounces
0.002 285 71
grains
avoirdupois pounds
0.000 142 86
grains
grams
0.064 798 91
grains
kilograms
0.000 064 798 91
grains
milligrams
64.798 910
grains
pennyweights
0.042
grains
scruples
0.05
grains
troy drams
0.016 6
grains
troy ounces
0.002 083 33
grains
troy pounds
0.000 173 61
grams
avoirdupois drams
0.564 383 39
grams
avoirdupois ounces
0.035 273 961
grams
avoirdupois pounds
0.002 204 622 6
grams
grains
15.432 361
grams
kilograms
0.001
grams
milligrams
1,000
grams
troy ounces
0.032 150 746 6
grams
troy pounds
0.002 679 23
hands (height of horse)
centimeters
10.16
hands (height of horse)
inches
4
hectares
acres
2.471 053 8
hectares
square feet
107,639.1
hectares
square kilometers
0.01
hectares
square meters
10,000
hectares
square miles
0.003 861 02
hectares
square yards
11,959.90
hundredweights, long
avoirdupois pounds
112
hundredweights, long
kilograms
50.802 345
hundredweights, long
long tons
0.05
hundredweights, long
metric tons
0.050 802 345
hundredweights, long
short tons
0.056
hundredweights, short
avoirdupois pounds
100
hundredweights, short
kilograms
45.359 237
hundredweights, short
long tons
0.044 642 86
hundredweights, short
metric tons
0.045 359 237
hundredweights, short
short tons
0.05
inches
centimeters
2.54
inches
feet
0.083 333 33
inches
meters
0.025 4
inches
millimeters
25.4
inches
yards
0.027 777 78
inches, cubic
bushels
0.000 465 025
inches, cubic
cubic centimeters
16.387 064
inches, cubic
cubic feet
0.000 578 703 7
inches, cubic
cubic meters
0.000 016 387 064
inches, cubic
cubic yards
0.000 021 433 47
inches, cubic
dry pints
0.029 761 6
inches, cubic
dry quarts
0.014 880 8
inches, cubic
gallons
0.004 329 0
inches, cubic
gills
0.138 528 1
inches, cubic
liquid ounces
0.554 112 6
inches, cubic
liquid pints
0.034 632 03
inches, cubic
liquid quarts
0.017 316 02
inches, cubic
liters
0.016 387 064
inches, cubic
milliliters
16.387 064
inches, cubic
minims (US)
265.974 0
inches, cubic
pecks
0.001 860 10
inches, square
square centimeters
6.451 600
inches, square
square feet
0.006 944 44
inches, square
square meters
0.000 645 16
inches, square
square yards
0.000 771 605
kilograms
avoirdupois drams
564.383 4
kilograms
avoirdupois ounces
35.273 962
kilograms
avoirdupois pounds
2.204 622 622
kilograms
grains
15,432.36
kilograms
grams
1,000
kilograms
long tons
0.000 984 2
kilograms
metric tons
0.001
kilograms
short hundredweights
0.022 046 23
kilograms
short tons
0.001 102 31
kilograms
troy ounces
32.150 75
kilograms
troy pounds
2.679 229
kilometers
meters
1,000
kilometers
statute miles
0.621 371 192
kilometers, square
acres
247.105 38
kilometers, square
hectares
100
kilometers, square
square meters
1,000,000
kilometers, square
statute miles
0.386 102 16
knots (nautical mi/hr)
kilometers/hour
1.852
knots (nautical mi/hr)
statute miles/hour
1.151
leagues, nautical
kilometers
5.556
leagues, nautical
nautical miles
3
leagues, statute
kilometers
4.828 032
leagues, statute
statute miles
3
links, square surveyor's
square centimeters
404.686
links, square surveyor's
square inches
62.726 4
links, surveyor's
centimeters
20.116 8
links, surveyor's
chains
0.01
links, surveyor's
inches
7.92
liters
bushels
0.028 377 59
liters
cubic feet
0.035 314 67
liters
cubic inches
61.023 74
liters
cubic meters
0.001
liters
cubic yards
0.001 307 95
liters
dekaliters
0.1
liters
dry pints
1.816 166
liters
dry quarts
0.908 082 98
liters
gallons
0.264 172 052
liters
gills (US)
8.453 506
liters
liquid ounces
33.814 02
liters
liquid pints
2.113 376
liters
liquid quarts
1.056 688 2
liters
milliliters
1,000
liters
pecks
0.113 510 4
meters
centimeters
100
meters
feet
3.280 839 895
meters
inches
39.370 079
meters
kilometers
0.001
meters
millimeters
1,000
meters
statute miles
0.000 621 371
meters
yards
1.093 613 298
meters, cubic
bushels
28.377 59
meters, cubic
cubic feet
35.314 666 7
meters, cubic
cubic inches
61,023.744
meters, cubic
cubic yards
1.307 950 619
meters, cubic
gallons
264.172 05
meters, cubic
liters
1,000
meters, cubic
pecks
113.510 4
meters, square
acres
0.000 247 105 38
meters, square
hectares
0.000 1
meters, square
square centimeters
10,000
meters, square
square feet
10.763 910 4
meters, square
square inches
1,550.003 1
meters, square
square yards
1.195 990 046
microns
meters
0.000 001
microns
inches
0.000 039 4
mils
inches
0.001
mils
millimeters
0.025 4
miles, nautical
kilometers
1.852 0
miles, nautical
statute miles
1.150 779 4
miles, statute
centimeters
160,934.4
miles, statute
feet
5,280
miles, statute
furlongs
8
miles, statute
inches
63,360
miles, statute
kilometers
1.609 344
miles, statute
meters
1,609.344
miles, statute
rods
320
miles, statute
yards
1,760
miles, square nautical
square kilometers
3.429 904
miles, square nautical
square statute miles
1.325
miles, square statute
acres
640
miles, square statute
hectares
258.998 811 033 6
miles, square statute
sections
1
miles, square statute
square kilometers
2.589 988 110 336
miles, square statute
square nautical miles
0.755 miles
miles, square statute
square rods
102,400
milligrams
grains
0.015 432 358 35
milliliters
cubic inches
0.061 023 744
milliliters
gallons
0.000 264 17
milliliters
gills (US)
0.008 453 5
milliliters
liquid ounces
0.033 814 02
milliliters
liquid pints
0.002 113 4
milliliters
liquid quarts
0.001 056 7
milliliters
liters
0.001
milliliters
minims
16.230 73
millimeters
inches
0.039 370 078 7
minims (US)
cubic inches
0.003 759 77
minims (US)
gills (US)
0.000 520 83
minims (US)
liquid ounces
0.002 083 33
minims (US)
milliliters
0.061 611 52
minims (US)
minims (British)
1.041
ounces, avoirdupois
avoirdupois drams
16
ounces, avoirdupois
avoirdupois pounds
0.062 5
ounces, avoirdupois
grains
437.5
ounces, avoirdupois
grams
28.349 523 125
ounces, avoirdupois
kilograms
0.028 349 523 125
ounces, avoirdupois
troy ounces
0.911 458 3
ounces, avoirdupois
troy pounds
0.075 954 86
ounces, liquid (US)
cubic feet
0.001 044 38
ounces, liquid (US)
centiliters
2.957 35
ounces, liquid (US)
cubic inches
1.804 687 5
ounces, liquid (US)
gallons
0.007 812 5
ounces, liquid (US)
gills (US)
0.25
ounces, liquid (US)
liquid drams
8
ounces, liquid (US)
liquid ounces (British)
1.041
ounces, liquid (US)
liquid pints
0.062 5
ounces, liquid (US)
liquid quarts
0.031 25
ounces, liquid (US)
liters
0.029 573 53
ounces, liquid (US)
milliliters
29.573 529 6
ounces, liquid (US)
minims
480
ounces, troy
avoirdupois drams
17.554 29
ounces, troy
avoirdupois ounces
1.097 143
ounces, troy
avoirdupois pounds
0.068 571 43
ounces, troy
grains
480
ounces, troy
grams
31.103 476 8
ounces, troy
pennyweights
20
ounces, troy
troy drams
8
ounces, troy
troy pounds
0.083 333 3
paces (US)
centimeters
76.2
paces (US)
inches
30
pecks (US)
bushels
0.25
pecks (US)
cubic feet
0.311 114
pecks (US)
cubic inches
537.605
pecks (US)
cubic meters
0.008 809 77
pecks (US)
cubic yards
0.011 522 74
pecks (US)
dekaliters
0.880 976 75
pecks (US)
dry pints
16
pecks (US)
dry quarts
8
pecks (US)
liters
8.809 767 5
pecks (US)
pecks (British)
0.968 9
pennyweights
grains
24
pennyweights
grams
1.555 173 84
pennyweights
troy ounces
0.05
pints, dry (US)
bushels
0.015 625
pints, dry (US)
cubic feet
0.019 444 63
pints, dry (US)
cubic inches
33.600 312 5
pints, dry (US)
dekaliters
0.055 061 05
pints, dry (US)
dry pints (British)
0.968 9
pints, dry (US)
dry quarts
0.5
pints, dry (US)
liters
0.550 610 47
pints, liquid (US)
cubic feet
0.016 710 07
pints, liquid (US)
cubic inches
28.875
pints, liquid (US)
deciliters
4.731 76
pints, liquid (US)
gallons
0.125
pints, liquid (US)
gills (US)
4
pints, liquid (US)
liquid ounces
16
pints, liquid (US)
liquid pints (British)
0.832 67
pints, liquid (US)
liquid quarts
0.5
pints, liquid (US)
liters
0.473 176 473
pints, liquid (US)
milliliters
473.176 473
pints, liquid (US)
minims
7,680
points (typographical)
inches
0.013 837
points (typographical)
millimeters
0.351 459 8
pounds, avoirdupois
avoirdupois drams
256
pounds, avoirdupois
avoirdupois ounces
16
pounds, avoirdupois
grains
7,000
pounds, avoirdupois
grams
453.592 37
pounds, avoirdupois
kilograms
0.453 592 37
pounds, avoirdupois
long tons
0.000 446 428 6
pounds, avoirdupois
metric tons
0.000 453 592 37
pounds, avoirdupois
quintals
0.004 535 92
pounds, avoirdupois
short tons
0.000 5
pounds, avoirdupois
troy ounces
14.583 33
pounds, avoirdupois
troy pounds
1.215 278
pounds, troy
avoirdupois drams
210.651 4
pounds, troy
avoirdupois ounces
13.165 71
pounds, troy
avoirdupois pounds
0.822 857 1
pounds, troy
grains
5,760
pounds, troy
grams
373.241 721 6
pounds, troy
kilograms
0.373 241 721 6
pounds, troy
pennyweights
240
pounds, troy
troy ounces
12
quarts, dry (US)
bushels
0.031 25
quarts, dry (US)
cubic feet
0.038 889 25
quarts, dry (US)
cubic inches
67.200 625
quarts, dry (US)
dekaliters
0.110 122 1
quarts, dry (US)
dry pints
2
quarts, dry (US)
dry quarts (British)
0.968 9
quarts, dry (US)
liters
1.101 221
quarts, dry (US)
pecks
0.125
quarts, dry (US)
pints, dry (US)
2
quarts, liquid (US)
cubic feet
0.033 420 14
quarts, liquid (US)
cubic inches
57.75
quarts, liquid (US)
deciliters
9.463 53
quarts, liquid (US)
gallons
0.25
quarts, liquid (US)
gills (US)
8
quarts, liquid (US)
liquid ounces
32
quarts, liquid (US)
liquid pints (US)
2
quarts, liquid (US)
liquid quarts (British)
0.832 67
quarts, liquid (US)
liters
0.946 352 946
quarts, liquid (US)
milliliters
946.352 946
quarts, liquid (US)
minims
15,360
quintals
avoirdupois pounds
220.462 26
quintals
kilograms
100
quintals
metric tons
0.1
rods
feet
16.5
rods
meters
5.029 2
rods
yards
5.5
rods, square
acres
0.006 25
rods, square
square meters
25.292 85
rods, square
square yards
30.25
scruples
grains
20
scruples
grams
1.295 978 2
scruples
troy drams
0.333
sections (US)
square kilometers
2.589 988 1
sections (US)
square statute miles
1
spans
centimeters
22.86
spans
inches
9
steres
cubic meters
1
steres
cubic yards
1.307 95
tablespoons
milliliters
14.786 76
tablespoons
teaspoons
3
teaspoons
milliliters
4.928 922
teaspoons
tablespoons
0.333 333
ton-miles, long
metric ton-kilometers
1.635 169
ton-miles, short
metric ton-kilometers
1.459 972
tons, gross register
cubic feet of permanently enclosed space
100
tons, gross register
cubic meters of permanently enclosed space
2.831 684 7
tons, long (deadweight)
avoirdupois ounces
35,840
tons, long (deadweight)
avoirdupois pounds
2,240
tons, long (deadweight)
kilograms
1,016.046 909 8
tons, long (deadweight)
long hundredweights
20
tons, long (deadweight)
metric tons
1.016 046 908 8
tons, long (deadweight)
short hundredweights
22.4
tons, long (deadweight)
short tons
1.12
tons, metric
avoirdupois pounds
2,204.623
tons, metric
kilograms
1,000
tons, metric
long hundredweights
19.684 130 3
tons, metric
long tons
0.984 206 5
tons, metric
quintals
10
tons, metric
short hundredweights
22.046 23
tons, metric
short tons
1.102 311 3
tons, metric
troy ounces
32,150.75
tons, net register
cubic feet of permanently enclosed space
for cargo and passengers
100
tons, net register
cubic meters of permanently enclosed space
for cargo and passengers
2.831 684 7
tons, shipping
cubic feet of permanently enclosed cargo space
42
tons, shipping
cubic meters of permanently enclosed cargo space
1.189 307 574
tons, short
avoirdupois pounds
2,000
tons, short
kilograms
907.184 74
tons, short
long hundredweights
17.857 14
tons, short
long tons
0.892 857 1
tons, short
metric tons
0.907 184 74
tons, short
short hundredweights
20
townships (US)
sections
36
townships (US)
square kilometers
93.239 572
townships (US)
square statute miles
36
miles, square statute
acres
640
miles, square statute
hectares
258.998 811 033 6
miles, square statute
square feet
27,878,400
miles, square statute
square meters
2,589,988.110 336
miles, square statute
square yards
3,097,600
yards
centimeters
91.44
yards
feet
3
yards
inches
36
yards
meters
0.914 4
yards
miles
0.000 568 18
yards, cubic
bushels
21.696 227
yards, cubic
cubic feet
27
yards, cubic
cubic inches
46,656
yards, cubic
cubic meters
0.764 554 857 984
yards, cubic
gallons
201.974 0
yards, cubic
liters
764.554 857 984
yards, cubic
pecks
86.784 91
yards, square
acres
0.000 206 611 6
yards, square
hectares
0.000 083 612 736
yards, square
square centimeters
8,361.273 6
yards, square
square feet
9
yards, square
square inches
1,296
yards, square
square meters
0.836 127 36
yards, square
square miles
0.000 000 322 830 6
The online Factbook is updated bi-weekly. ISSN 1553-8133
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