ORCCA Unit Conversions

Appendix A Unit Conversions

Table A.0.1. Length Unit Conversion Factors

Units of Length in the US/Imperial System	Units of Length in the Metric System	System to System Length Conversions
$1$ foot () ${}=12$ inches (in)	$1$ meter () ${}=1000$ millimeters (mm)	$1$ inch () ${}=2.54$ centimeters (cm)
$1$ yard () ${}=3$ feet (ft)	$1$ meter () ${}=100$ centimeters (cm)	$1$ meter () ${}\approx3.281$ feet (ft)
$1$ yard () ${}=36$ inches (in)	$1$ meter () ${}=10$ decimeters (dm)	$1$ meter () ${}\approx1.094$ yard (yd)
$1$ mile () ${}=5280$ feet (ft)	$1$ dekameter () ${}=10$ meters (m)	$1$ mile () ${}\approx1.609$ kilometer (km)
	$1$ hectometer () ${}=100$ meters (m)
	$1$ kilometer () ${}=1000$ meters (m)

Table A.0.2. Area Unit Conversion Factors

Units of Area in the US/Imperial System	Units of Area in the Metric System	System to System Area Conversions
$1$ acre ${}=43560$ square feet (ft²)	$1$ hectare () ${}=10000$ square meters (m²)	$1$ hectare () ${}\approx2.471$ acres
$640$ acres ${}=1$ square mile (mi²)	$100$ hectares () ${}=1$ square kilometer (km²)

Table A.0.3. Volume Unit Conversion Factors

Units of Volume in the US/Imperial System	Units of Volume in the Metric System	System to System Volume Conversions
$1$ tablespoon () ${}=3$ teaspoon (tsp)	$1$ cubic centimeter () ${}=1$ cubic centimeter (cm³)	$1$ cubic inch () ${}\approx16.39$ milliliters (mL)
$1$ fluid ounce () ${}=2$ tablespoons (tbsp)	$1$ milliliter () ${}=1$ cubic centimeter (cm³)	$1$ fluid ounce () ${}\approx29.57$ milliliters (mL)
$1$ cup () ${}=8$ fluid ounces (fl oz)	$1$ liter () ${}=1000$ milliliters (mL)	$1$ liter () ${}\approx1.057$ quarts (qt)
$1$ pint () ${}=2$ cups (c)	$1$ liter () ${}=1000$ cubic centimeters (cm³)	$1$ gallon () ${}\approx3.785$ liters (L)
$1$ quart () ${}=2$ pints (pt)
$1$ gallon () ${}=4$ quarts (qt)
$1$ gallon () ${}=231$ cubic inches (in³)

Table A.0.4. Weight/Mass Unit Conversion Factors

Units of Mass/Weight in the US/Imperial System	Units of Mass/Weight in the Metric System	System to System Mass/Weight Conversions
$1$ pound () ${}=16$ ounces (oz)	$1$ gram () ${}=1000$ milligrams (mg)	$1$ ounce () ${}\approx28.35$ grams (g)
$1$ ton () ${}=2000$ pounds (lb)	$1$ kilogram () ${}=1000$ grams (g)	$1$ kilogram () ${}\approx2.205$ pounds (lb)
	$1$ metric ton () ${}=1000$ kilograms (kg)

Table A.0.5. Time Unit Conversion Factors

Precise Units of Time	Imprecise Units of Time	Units of Time in the Metric System
$1$ week () ${}=7$ days (d)	$1$ year () ${}\approx12$ months (mo)	$1$ second () ${}=1000$ milliseconds (ms)
$1$ day () ${}=24$ hours (h)	$1$ year () ${}\approx52$ weeks (wk)	$1$ second () ${}=10^6$ microseconds (µs)
$1$ hour () ${}=60$ minutes (min)	$1$ year () ${}\approx365$ days (d)	$1$ second () ${}=10^9$ nanoseconds (ns)
$1$ minute () ${}=60$ seconds (s)	$1$ month () ${}\approx30$ days (d)

Table A.0.6. Computer Storage/Memory Conversion Factors