Conversion Tables
These extremely useful tables give SI units and conversion factors for practically every engineering quantity you are ever likely to need.
Unit Conversion Factors
 
 
Select a property from the drop-down menu:
To Convert From To Multiply By
[Back to top]

ACCELERATION

feet per second per second centimeters per second per second
meters per second per second		 30.480
0.30480
free fall (standard) meters per second per second 9.8067
kilometers per hour per second centimeters per second per second
feet per second per second
meters per second squared		 27.778
0.9113
0.27778
[Back to top]

ANGULAR

circumferences radians 6.283
degrees grade
radians		 1.111
0.017453
degrees per second radians per second
revolutions per minute
revolutions per second 		0.017453
0.16667
0.0027778
minutes radians 0.002909
radians degrees (angular) 57.296
radians per second degrees per second (angular)
revolutions per minute		 57.296
9.549
revolutions per minute degrees per second
radians per second		 6
0.01472
[Back to top] AREA
acres square feet
square meters
hectares		 43560
4046.9
0.40469
circular mils square inches 0.000007854
hectares acres
square feet
square meters		 2.4710
107639
10000
square centimeters square inches 0.1550
square feet acres
square meters		 0.000022956
0.092903
square inches square centimeters 6.4516
square kilometers acres
square miles		 247.10
0.38610
square meters acres
square feet		 0.00024710
10.764
square miles acres
square kilometers		 640
2.590
square yards acres
square meters		 0.00020661
0.83613
[Back to top]

CANDLEPOWER

foot candles lumens per square meter 10.764
[Back to top] CAPACITY, DISPLACEMENT
cubic inches per revolution liters per revolution
milliliters per revolution		 0.01639
16.39
[Back to top]

DENSITY, MASS/VOLUME

grams per cubic centimeter kilograms per cubic meter
pounds per cubic inch
pounds per cubic foot		 0.001
0.03613
62.427
pounds-mass per cubic foot kilograms per cubic meter 16.018
pounds per cubic foot grams per cubic centimeter
kilograms per cubic meter
pounds per cubic inch		 0.016018
16.018
0.0005787
pounds per cubic inch grams per cubic centimeter
kilograms per cubic meter
newtons per meter		 27.68
27.680
1728
[Back to top]
ENERGY AND WORK
British thermal units joules 1055
British thermal units per second watts 1.055
British thermal units per minute horsepower
watts		 0.02358
17.58
British thermal units per hour watts 0.2931
calories British thermal units
foot-pounds
joules
kilogram-meters
watt-hours		 0.0039683
3.088
4.1868
0.4265
0.001163
ergs joules 0.0000001
foot-pounds-force British thermal units
calories
horsepower hours
joules
kilocalories
kilogram-force meters
kilowatt hours		 0.001285
0.3238
0.0000005050
1.3558
0.0003238
0.13825
0.0000003766
horsepower British thermal units per minute
foot-pounds-force per minute
foot-pounds-force per second
kilocalories per minute
kilowatts
horsepower (metric)
watts		 42.43
33000
550
10.69
0.7457
1.0139
745.7
horsepower-boiler British thermal units per horse
kilowatts
pounds of water evaporated per hour at 212°F		 33479
9.8095
34.5
horsepower hours British thermal units
foot-pounds-force
joules
kilocalories
kilogram-force meters
kilowatt hours		 2.545
1980000
2684500
641.5
273200
0.7457
joules British thermal units
calories
foot-pounds-force
watt-hours		 0.0009484
0.2390
0.73756
0.00027778
kilowatts British thermal units per minute
foot-pounds-force per minute
foot-pounds-force per second
horsepower
kilocalories per minute		 56.92
44254
737.6
1.3410
14.34
kilowatt hours British thermal units
foot-pounds-force
horsepower hours
joules
kilocalories
kilograms-force meters		 3413
2655000
1.3410
3.600000
860
367100
pounds-force kilograms-force
newtons		 0.45359
4.4482
tons of refrigeration British thermal units per hour
British thermal units per 24 hours		 12000
288000
watts British thermal units per minute
foot-pounds-force per second
foot-pounds-force per minute
horsepower
joules per second
kilocalories per minute		 0.05691
0.73756
44.254
0.0013410
1.0
0.014340
watt-hours British thermal units
foot-pounds-force
horsepower hours
joules
kilocalories
kilograms-force-meters		 3.413
2665
0.0013410
3600
0.8604
367.10
There are several definitions of the Btu, and the values of applicable and/or equivalent factors
may vary slightly depending on the definition used. For this reason, three or four significant figures
are given on this page, and in most cases provide a value near to most definitions of the Btu.
However, as always in making calculations of high accuracy, one should reference the appropriate
lists and handbooks of standards.
[Back to top]

ENERGY/AREA TIME
Btu/cubic feet second watts per square meter 11348
Btu/cubic feet hour watts per square meter 3.1525
[Back to top]
FLOW RATE MASS
pounds per minute kilograms per minute 0.4536
[Back to top]

FLOW RATE VOLUME
cubic feet per minute cubic centimeters per second
cubic meters per second
cubic meters per hour
liters per second
gallons (US) per second
pounds of water per minute (at 68°F)		 471.9
0.0004719
1.699
0.4719
0.2247
62.32
cubic feet per second cubic meters per second
cubic meters per minute
cubic meters per hour
gallons (US) per minute
gallons (imp) per hour
liters		 0.028317
1.699
101.9
448.8
646315
28.32
cubic meters per hour cubic meters per minute
cubic meters per second
gallons (US) per minute
liters per second		 0.016667
0.00027778
4.4033
0.27778
cubic meters per second cubic meters per hour
gallons (US) per minute		 3600
15850
gallons (US) per minute cubic meters per second
cubic meters per minute
cubic meters per hour
cubic feet per second
cubic feet per hour
liters per second		 0.000063090
0.0037854
0.2771
0.002228
8.021
0.06309
liters per minute cubic feet per second
liters per second
gallons (US) per second
gallons (US) per minute
gallons (imp) per minute		 0.0005885
0.01667
0.004403
0.26418
0.003666
liters per second cubic meters per second
cubic meters per minute
cubic meters per hour
liters per minute
gallons (US) per minute
gallons (imp) per minute		 0.001
0.06
3.600
60
15.85
13.20
pounds of water per minute at 60°F cubic centimeters per second
cubic feet per second
cubic meters per minute
kilograms per second		 7.5667
0.0002675
0.00045398
0.0075599
standard cubic feet per minute cubic meters per hour at STP
liters per second at STP		 1.6957
0.47103
stokes square feet per second
square meters per second		 0.001076
0.0001
tons (short) of water per 24 hours at 60°F cubic feet per hour
cubic meters per hour
gallons (US) per minute
pounds of water per hour		 1.338
0.03789
0.1668
83.333
[Back to top] FORCE
dynes newtons 0.00001
newtons
grams-force 0.0098066
kilograms-force newtons
pounds-force		 9.8066
2.2046
kiloponds newtons
kilograms-force
pounds-force
poundals
kips		 9.807
1
2.2046
70.932
0.002205
kips newtons
kilograms-force
pounds-force
poundal
kilopond		 4448
453.6
1000
32174
453.6
grams-force per centimeter newtons per meter
pounds-force per inch		 98.07
0.005600
kilograms-force per meter newtons
pounds-force per foot		 9.8066
0.6721
newtons dynes
kilograms-force
poundals
pounds-force		 100000
0.10197
7.2330
0.2248
poundals newtons 0.13826
pounds-force newtons 4.448
[Back to top]

LENGTH
centimeters inches 0.3937
fathoms feet
meters		 6
1.8288
feet centimeters
inches
meters
yards		 30.480
12
0.30480
0.3333
inches centimeters
meters
millimeters
micrometers		 2.540
0.02540
25.40
25.4
kilometers feet
miles		 3280.8
0.62137
meters feet
inches
yards		 3.2808
39.370
1.0936
micrometers meters 0.000001
millimeters inches 0.039370
mills millimeters 0.0254
miles feet
kilometers
meters
yards		 5280
1.6093
1609.3
1760
statute miles kilometers 1.609
yards meters 0.91440
[Back to top] MASS/WEIGHT
drams (avoir) grains
grams
ounces		 27.344
1.7718
0.0625
grains grams
ounces (avoir)		 0.0648
0.0022857
grams grains
ounces (avoir)
pounds (avoir)		 15.432
0.035274
0.0022046
kilograms pounds
tons (short)		 2.2046
0.0011023
metric tons (tonnes) kilograms
pounds		 1000
2204.6
ounces (avoir) drams (avoir)
grains
grams
kilograms
pounds-avoir
tons (long)
metric tons		 16
437.5
28.3495
0.028350
0.06250
0.00002790
0.000028350
pounds (avoir) drams (avoir)
grains
grams
kilograms
ounces (avoir)
metric tons
tons (long)
tons (short)		 256
7000
453.59
0.45359
16
0.00045359
0.00044643
0.0005
tons (long) kilograms
metric tons
pounds-avoir
tons (short)		 1016.0
1.0160
2240
1.120
tons (short) kilograms
pounds-avoir
tons (long)
metric tons		 907.18
2000
0.89286
0.9072
short ton metric ton/tonne 0.9072
[Back to top] POWER
Btu/hour watt 0.2931
Btu/second watt 1055
Horsepower kilowatt 0.746
[Back to top] PRESSURE AND STRESS
atmosphere bars
centimeters of mercury at 32F
feet of water at 68F
inches of mercury at 32F
kilograms-force per square centimeter
kilograms-force per square meter
kilopascals
pounds-force per square inch
tons-force (short) per square foot
torr		 1.01325
76.0
33.96
29.921
1.0332
103322
101.325
14.696
1.0581
760
bars kilopascals 100
centimeters of mercury atmospheres
bars
feet of water at 68°F
inches of water at 68°F
kilograms-force per square centimeter
pounds-force per square inch
torr		 0.013158
0.01333
0.4468
5.362
0.19337
27.85
10
feet of water (at 68°F) atmospheres
bars
inches of mercury (at 0°C)
kilograms-force per square centimeter
kilopascals
pounds-force per square inch
pounds-force per square foot		 0.02945
0.02984
0.8811
0.03042
2.984
0.4328
62.32
inches of mercury at 0°C atmospheres (standard)
bars
feet of water at 68°F
inches of water at 68°F
kilograms-force per square centimeter
kilograms-force per square meter
kilopascals
millimeters of mercury
pounds-force per square foot
pounds-force per square inch		 0.00342
0.033864
1.135
13.62
0.034532
345.32
3.3864
25.40
70.73
0.4912
inches of water at 68°F atmosphere
bars
inches of mercury
kilograms-force per square centimeter
kilopascals
ounces-force per square inch
pounds-force per square foot
pounds-force per square inch		 0.002454
0.002487
0.07342
0.002535
0.2487
0.5770
5.193
0.03606
kilograms-force per square centimeter atmospheres
bars
feet of water at 68°F
inches of mercury at 0°C
kilopascals
pounds-force per square foot
pounds-force per square inch		 0.9678
0.98066
32.87
28.96
98.066
2048
14.223
kilograms-force per square millimeter kilograms-force per square meter
megapascals		 1000000
9.8066
kilograms per square meter pascals 9.807
kilopascals dynes per square centimeter
feet of water at 68°F
inches of mercury at 32°F
inches of water at 68°F
kilograms-force per square centimeter
pascals
pounds-force per square inch		 10000
0.3351
0.2953
4.021
0.010197
1000
0.1450
kips per square inch kilopascals
kilograms-force per square centimeter
bars
pounds per square inch		 6894.8
70.307
68.94
1000
megapascals kilograms-force per square millimeter
kilograms-force per square centimeter
kilopascals
pascals
pounds-force per square inch		 0.10197
10.197
1000
1000000
145.0
millibars pascals 100
millimeters of mercury at 0°C bars
feet of water at 68°F
inches of mercury
inches of water at 68°F
kilograms per square centimeter
pascals
pounds per square inch		 0.0013332
0.004680
0.03937
0.53616
0.0013595
133.32
0.0193368
ounces-force per square inch grams-force per square centimeter
pascals
pounds-force per square inch		 4.395
43.1
0.06250
pascals bars
dynes per square centimeter
grams-force per square centimeter
kilograms-force per square centimeter
kilopascals
newtons per square meter
pounds-force per square inch		 0.00001
10.0
0.010197
0.000010197
0.001
1.0
0.0001450
poise centipoises
pascal-seconds
pound-force-seconds per square foot
pounds per foot-second		 100
0.1000
0.0020886
0.06721
pounds-force per square foot feet of water at 68°F
kilograms-force per square centimeter
kilopascals
pascals
pounds-force per square inch		 0.01605
0.0004882
0.0047880
47.880
0.0069444
pounds-force per square inch atmospheres
feet of water at 68°F
inches of water at 68°F
inches of mercury at 0°F
kilograms force per square centimeter
kilopascals		 0.06805
2.311
27.73
2.036
0.07031
6.8948
pounds per square foot kilograms per square meter 4.8824
pounds per square inch pascals
kilopascals
megapascals		 6895
6.895
0.006895
[Back to top] THERMAL CONDUCTIVITY
Btu . inch . hour . feet2 . °F watt per meter2 °K 0.1442
[Back to top] TORQUE: BENDING MOMENT
pound feet newton meters 1.356
kilogram meters newton meters 9.807
[Back to top] VELOCITY
centimeters per second feet per second
feet per minute
miles per hour
kilometers per hour
meters per minute		 0.03281
1.9685
0.02237
0.03600
0.60000
feet per minute centimeters per second
kilometers per hour
meters per minute
meters per second
miles per hour		 0.5080
0.01829
0.30480
0.00508
0.01136
feet per second centimeters per second
kilometers per hour
meters per minute
meters per second
miles per hour		 30.480
1.097
18.29
0.30480
0.6818
international knots meters per second
miles per hour		 0.5144
1.1516
kilometers per hour centimeters per second
feet per second
feet per minute
international knots
meters per minute
meters per second
miles per hour		 27.778
0.9113
54.68
0.53996
16.667
0.27778
0.6214
kilometers per second miles per minute 37.28
meters per minute centimeters per second
feet per minute
feet per second
kilometers per hour
miles per hour		 1.6667
3.2808
0.05468
0.0600
0.03728
meters per second feet per minute
feet per second
kilometers per hour
kilometers per minute
miles per hour
miles per minute		 196.8
3.281
3.600
0.0600
2.237
0.03728
miles per hour centimeters per second
feet per minute
feet per second
international knots
kilometers per hour
meters per minute		 44.70
88
1.4667
0.8690
1.6093
26.82
[Back to top] VOLUME
acre-feet cubic feet
gallons (US)
cubic meters		 43.560
325851
1233.5
barrels (US liquid) gallons (US) 31.5
barrels (oil) cubic meters
gallons of oil
cubic meters		 0.11924
42
0.15899
cubic centimeters cubic inches
cubic feet
cubic yards
gallons (US)
gallons (imp)
liters		 0.06102
0.000035315
0.000001308
0.0002642
0.00022
0.001
cubic feet cubic centimeters
cubic meters
cubic inches
cubic yards
gallons (US)
gallons (imp)
liters		 28317
0.028317
1728
0.03704
7.4805
6.229
28.32
cubic inches cubic centimeters
cubic feet
cubic meters
cubic yards
gallons (US)
gallons (imp)
liters		 16.387
0.0005787
0.000016387
0.00002143
0.004329
0.03605
0.016387
cubic meters cubic inches
cubic feet
cubic yards
gallons (US)
gallons (imp)
liters		 61024
35.315
1.3080
264.17
219.97
1000
cubic yards cubic centimeters
cubic feet
cubic inches
cubic meters
gallons (US)
gallons (imp)
liters		 764550
27
46.656
0.76455
201.97
168.17
764.55
fluid ounces (US) cubic inches
liters		 1.8046
0.02957
gallons (imp) cubic centimeters
cubic meters
cubic feet
cubic yards
gallons (US)
liters
pounds of water at 62°F		 4546.1
0.0045461
0.16054
0.005946
1.20094
4.5461
10.000
gallons (US) cubic centimeters
cubic meters
cubic inches
cubic feet
cubic yards
pints (liquid)
quarts (liquid)
gallons (imp)
liters
pounds of water at 60°F		 3785.4
0.0037854
231
0.13368
0.0049515
8
4
0.8327
3.7854
8.338
liters cubic centimeters
cubic feet
cubic inches
cubic meters
cubic yards
gallons (US)
gallons (imp)		 1000
0.035315
61.024
0.001
0.001308
0.26418
0.2200
pounds-mass of water at 60°F cubic centimeters
cubic feet
cubic inches
gallons (US)
liters		 454.00
0.01603
27.70
0.11993
0.45398
quarts (dry) cubic centimeters
cubic inches
cubic meters		 1101.2
67.20
0.0011012
quarts (liquid) cubic centimeters
cubic inches
liters		 946.35
57.75
0.94635
[Back to top] WATER HARDNESS
grains per gallon (imp) grams per cubic meter
kilograms per cubic meter
parts per million by weight in water		 14.25
0.01425
14.25
grains per gallon (US) grams per cubic meter
kilograms per cubic meter
parts per million by weight in water
pounds per million gallons		 17.118
0.017118
17.118
142.9
grains per liter grains per US gallon
parts per million by mass weight in water
pounds per cubic foot
pounds per 1000 gallons (US)		 58.417
1000
0.0622427
8.3544
milligrams per liter parts per million 1.0
parts per million by mass grains per gallon (US) at 60°F
grains per gallon (imp) at 62°F
grams per cubic meter at 15°C
milligrams per liter
pounds per million gallons (US) at 60°F		 0.0583
0.0700
0.9991
1.0
8.328