Gardening Basics: Measurement Conversion

Gardening Basics: Measurement Conversion

We often find it quite confusing when referring to botanical research papers, cultivation guides and other resources from various authors around the world – each using their culture’s preferred system of measurement. In light of this, here’s a (relatively) basic guide to converting between the various Imperial and Metric measurement systems; hopefully it can help you to get on with the most important part of the whole process – getting out in the garden and actually growing some plants!

This guide covers measuring area, capacity, length, volume and weight. Be aware that this can be a little complicated; for example, the UK weighs with a ‘long ton’, the USA a ‘short ton’, which are definitely not the same thing! Further, when measuring capacity, it’s useful to know that many Imperial measurements of liquid volume (e.g. a pint) are different, dependent on whether you’re in the UK, USA or elsewhere. At least Metric units are always the same, wherever you might be!

With that said, if you’re confused about any area, length, volume, capacity or weight-related Imperial and/or Metric conversions, read on…


Length Conversions

Metric Units of Length and Their Abbreviations

1 millimetre = 1 mm
1 centimetre = 1 cm
1 decimetre = 1 dm
1 metre = 1 m
1 decametre = 1 dcm
1 hectometre = 1 hm
1 kilometre = 1 km

Metric Length Conversions

1 centimetre = 10 millimetres
1 decimetre = 10 centimetres
1 metre = 100 centimetres
1 decametre = 10 metres
1 hectometre = 100 metres
1 kilometre = 1,000 metres

Imperial Units of Length and Their Abbreviations

1 inch = 1 in
1 foot = 1 ft
1 yard = 1 yd
1 chain = 1 ch
1 furlong = 1 fur
1 mile = 1 mi

Imperial Length Conversions

1 foot = 12 inches
1 yard = 3 feet
1 chain = 22
1 furlong = 220 yards (or 10 chains)
1 mile = 1,760 yards (or 8 furlongs)

Metric to Imperial Length Conversions

1 millimetre = 0.0394 inches
1 centimetre = 39.370 inches
1 metre = 3.281 feet
1 metre = 1.094 yards
1 metre = 1,093.6 yards
1 kilometre = 0.621 mile

Imperial to Metric Length Conversions

1 inch = 2.54 centimetres
1 foot = 30.48 centimetres
1 yard = 91.44 centimetres
1 yard = 0.914 metres
1 mile = 1,609.3 metres
1 mile = 1.609 kilometres


Area Conversions

Metric Units of Area and Their Abbreviations

1 square millimetre = 1 sq. mm
1 square centimetre = 1 sq. cm
1 square decimetre = 1 sq. dm
1 square metre = 1 sq. m
1 square decametre = 1 sq. dcm
1 square hectometre = 1 sq. hm
1 hectare = 1 ha
1 square kilometre = 1 sq. km

Metric Area Conversions

1 sq. centimetre = 100 sq. millimetres
1 sq. metre = 10,000 sq. centimetres
1 hectare  = 10,000 sq. metres
1 sq. km = 100 hectares
1 sq. km = 1,000,000 sq. metres

Imperial Units of Area and Their Abbreviations

1 square inch = 1 sq. in
1 square foot = 1 sq. ft
1 square yard = 1 sq. yd
1 square acre = 1 sq. acre
1 square mile = 1 sq. mi

Imperial Area Conversions

1 sq. foot = 144 sq. inches
1 sq. yard = 1,296 sq. inches
1 sq. yard = 9 sq. feet
1 acre = 4,840 sq. yards
1 sq. mile = 640 acres

Metric to Imperial Area Conversions

1 sq. centimetre = 0.155 sq. inches
1 sq. metre = 10.764 sq. feet
1 sq. metre = 1.196 sq. yards
1 hectare = 2.471 acres
1 hectare = 0.00386 sq. miles

Imperial to Metric Area Conversions

1 sq. inch = 6.4516 sq. centimetres
1 sq. foot = 929.0304 sq. centimetres
1 sq. foot = 0.09290 sq. metres
1 sq. yard = 0.83613 sq. metres
1 acre = 0.40469 hectares
1 sq. mile = 258.99881 hectares


Volume Conversions

Metric Units of Volume and Their Abbreviations

1 cubic millimetre = 1 cu mm
1 cubic centimetre = 1 cu cm
1 cubic metre = 1 cu m

Metric Volume Conversions

1 cubic centimetre = 1,000 cubic millimetres
1 cubic metre = 1,000,000 cubic centimetres

Imperial Units of Volume and Their Abbreviations

1 cubic inch = 1 cu in
1 cubic foot = 1 cu ft
1 cubic yard = 1 cu yd

Imperial Volume Conversions

1 cubic foot = 1,728 cubic inches 
1 cubic yard = 46,656 cubic inches
1 cubic yard = 27 cubic feet

Metric to Imperial Volume Conversions

1 cubic centimetre = 0.06102 cubic inches
1 cubic metre = 35.31467 cubic feet 
1 cubic metre = 1.30795 cubic yards

Imperial to Metric Volume Conversions

1 cubic inch = 16.38706 cubic centimetres 
1 cubic foot = 0.02832 cubic metres
1 cubic foot = 28,316.846 cubic centimetres
1 cubic yard = 0.76455 cubic metres


Weight Conversions

Don’t forget that the UK weighs with a ‘long ton’, the USA a ‘short ton’ – two different units of measurement, just to confuse you!

Metric Units of Weight and Their Abbreviations

1 milligram = 1 mg
1 gram = 1 g
1 kilogram = 1 kg
1 tonne = 1 Mg

Metric Weight Conversions

1 gram = 1,000 milligrams
1 kilogram = 1,000 grams 
1 tonne = 1,000 kilograms

Imperial Units of Weight and Their Abbreviations

1 drams = 1 dr
1 ounce = 1 oz 
1 pound = 1 lb
1 stone = 1 st
1 quarter = 1 qr
1 hundredweight = 1 cwt
1 ton, long = 1 ton

Imperial Weight Conversions

1 ounce = 16 drams 
1 pound = 16 ounces 
1 stone = 14 pounds
1 quarter = 2 stone
1 hundredweight = 8 stone
1 ton, long = 160 stone

Metric to Imperial Weight Conversions

1 gram = 0.0353 ounces
1 kilogram = 2.205 pounds
1 kilogram = 35.274 ounces
1 tonne = 0.984 ton, long
1 tonne = 157.47 stone

Imperial to Metric Weight Conversions

1 ounce = 28.350 grams
1 pound = 453.59 grams
1 pound = 0.454 kilograms
1 stone = 6.350 kilograms
1 hundredweight = 50.802 kilograms
1 ton, long = 1.016 tonnes
1 ton, short = 0.907 tonnes


Capacity Conversion

Many Imperial measurements of liquid volume (for example, a pint) are different, dependent on whether you’re in the UK, USA or elsewhere. Simply, 1 UK gallon = 4 UK quarts = 8 UK pints = 160 UK fluid ounces. The Imperial measurements listed in this section all refer to UK units only!

Metric Units of Capacity and Their Abbreviations

1 millilitre = 1 ml
1 centilitre = 1 cl
1 litre = 1 l
1 kilolitre = 1 kl

Metric Capacity Conversions

1 centilitre = 10 millilitres
1 litre = 1,000 millilitres
1 kilolitre = 1,000 litres

Imperial Units of Capacity and Their Abbreviations

1 fluid dram = 1 fl dr
1 fluid ounce = 1 fl oz
1 gill = 1 gi
1 pint = 1 pt
1 quart = 1 qt
1 gallon = 1 gal
1 barrel, bulk = 1 barrel

Imperial Capacity Conversions

1 fluid ounce = 8 fluid drams
1 gill = 5 fluid ounces
1 pint = 4 gills
1 pint = 20 fluid ounces
1 quart = 2 pints
1 gallon = 4 quarts
1 gallon = 8 pints
1 barrel, bulk = 36 gallons

Metric to Imperial Capacity Conversions

1 millilitre = 0.0352 fluid ounces
1 litre = 35.195 fluid ounces
1 litre = 1.760 pints
1 kilolitre = 6.110 barrels
1 kilolitre = 219.97 gallons

Imperial to Metric Capacity Conversions

1 fluid ounce = 28.41 millilitres
1 pint = 568.26 millilitres
1 pint = 0.568 litres
1 gallon = 4.546 litres
1 barrel = 163.66 litres