# Imperial units

Like metric system units, imperial units are used to measure quantities such as mass, distance, area, volume/capacity and speed.

They include pounds, yards, square and cubic yards, imperial gallons and miles per hour.

## Converting between imperial units

### Mass

 Conversion factor Example Imperial tons to stones(imperial tons to st) x 160 1 imperial ton= 1 x 160= 160 stones Stones to imperial tons(st to imperial tons) ÷ 160 160 stones= 160 ÷ 160= 1 imperial ton Stones to pounds(st to lb) x 14 1st = 1 x 14 = 14lb Pounds to stones(lb to st) ÷ 14 14lb = 14 ÷ 14 = 1st Pounds to ounces(lb to oz) x 16 1lb = 1 x 16 = 16oz Ounces to pounds(oz to lb) ÷ 16 16oz = 16 ÷ 16 = 1lb ### Distance (length/height/width)

 Conversion factor Example Miles to yards(miles to yd) x 1760 1 mile = 1 x 1760 = 1760yd Yards to miles(yd to miles) ÷ 1760 1760yd = 1760 ÷ 1760 = 1 mile Yards to feet(yd to ft) x 3 1yd = 1 x 3 = 3ft Feet to yards(ft to yd) ÷ 3 3ft = 3 ÷ 3 = 1yd Feet to inches (ft to in) x 12 1ft = 1 x 12 = 12in Inches to feet (in to ft) ÷ 12 12in = 12 ÷ 12 = 1ft

### Area

 Conversionfactor Example Acres to square yards(ac to yd²) x 4840 1ac = 1 x 4840 = 4840yd² Square yards to acres(yd² to ac) ÷ 4840 4840yd² = 4840 ÷ 4840 = 1ac Square yardsto square feet(yd² to ft²) x 9 1yd² = 1 x 9 = 9ft² Square feetto square yards(ft² to yd²) ÷ 9 9ft² = 9 ÷ 9 = 1yd² Square feetto square inches(ft² to in²) x 144 1ft² = 1 x 144 = 144in² Square inchesto square feet(in² to ft²) ÷ 144 144in² = 144 ÷ 144 = 1ft²

Note

• 1yd² = 1yd x 1yd = 3ft x 3ft = 9ft²
• 1ft² = 1ft x 1ft = 12in x 12in = 144in²

### Volume / capacity

 Conversionfactor Example Cubic yards to cubic feet(yd³ to ft³) x 27 1yd³ = 1 x 27 = 27ft³ Cubic feet to cubic yards(ft³ to yd³) ÷ 27 27ft³ = 27 ÷ 27= 1yd³ Cubic feet to cubic inches(ft³ to in³) x 1728 1ft³ = 1 x 1728 = 1728in³ Cubic inches to cubic feet(in³ to ft³) ÷ 1728 1728in³ = 1728 ÷ 1728 = 1ft³ Imperial gallonsto imperial pints(imp gal to imp pt) x 8 1 imp gal = 1 x 8 = 8 imp pt Imperial pintsto imperial gallons(imp pt to imp gal) ÷ 8 8 imp pt = 8 ÷ 8 = 1 imp gal

Note

• 1yd³ = 1yd x 1yd x 1yd = 3ft x 3ft x 3ft = 27ft³
• 1ft³ = 1ft x 1ft x 1ft = 12in x 12in x 12in = 1728in³

Also

• imperial gallon ~4.546l, imperial pint ~0.568l
• US gallon ~3.785l, US pint ~ 0.473l

### Speed

 Conversionfactor Example Miles per hourto yards per second(yd/s to mph) ÷ 2.045(approx) 2.045mph= 2.045 ÷ 2.045= 1yd/s Yards per secondto miles per hour(yd/s to mph) x 2.045(approx) 1yd/s = 1 x 2.045 = 2.045mph Miles per hourto feet per second(mph to ft/s) ÷ 0.682(approx) 0.682mph= 0.682 ÷ 0.682= 1ft/s Feet per secondto miles per hour(ft/s to mph) x 0.682(approx) 1ft/s = 1 x 0.682 = 0.682mph

## What about switching between metric and imperial units?

Okay, now you know about metric and imperial units, get ready to learn how to convert metric to imperial and imperial to metric.

For more on metric vs imperial click:

What is the metric system?

Metric to imperial conversion