Comprehensive Metric and Imperial Conversion Tables

Ian C. Langtree - Writer/Editor for Disabled World (DW)
Published: 2017/12/20 - Updated: 2025/05/19
Publication Type: Conversion, Calculation
Category Topic: Medical Calculators and Charts - Academic Publications

Page Content: Synopsis - Introduction - Main - Insights, Updates

Synopsis: This information presents a comprehensive set of metric and imperial conversion formula tables, offering clear, practical guidance for converting between measurement systems. It includes conversion factors for length, area, volume, weight, and temperature, such as 1 inch equaling 2.54 centimeters, 1 mile equaling 1.609344 kilometers, and the formula for converting Celsius to Fahrenheit. The resource also highlights differences between U.S. customary and British imperial units, like the variance between U.S. and British gallons. Its straightforward format makes it particularly useful for individuals who may find digital tools challenging, including seniors and those with disabilities, by facilitating manual calculations without the need for complex software - Disabled World (DW).

Introduction

Our handy conversion tables show you the formulas to convert from metric system measurements to the imperial system and visa versa allowing you to do your own calculations for the conversion you need.

Main Content

Metric System

The metric system is a decimalised system of measurement in the sense that all multiples and sub-multiples of the base units are factors of powers of ten of the unit. Fractions of a decimal unit are rarely used.

The metric system, and metre was first fully described by Englishman John Wilkins in 1668 in a treatise presented to the Royal Society some 120 years before the French adopted the system. It is believed that the system was transmitted to France from England via the likes of Benjamin Franklin. In the U.S. Americans frequently spell 'metre' as 'meter', and 'litre' as 'liter'; however 'metre' and 'litre' are the official BIPM names for these units.

Imperial System

Imperial units are the measurement units that were historically used in the British Commonwealth countries. They were very similar, but not identical, to the units that are still predominantly used in the United States. Some of the differences are:

1 U.S. fluid ounce = 1.041 British fluid ounces
1 British fluid ounce = 0.961 U.S. fluid ounce
1 U.S. gallon = 0.833 British Imperial gallon
1 British Imperial gallon = 1.201 U.S. gallons

Our handy conversion tables below show you the formulas to convert from metric system measurements to the imperial system and visa versa allowing you to do your own calculations for the conversion you need. Measurement conversions include weight, mass, length, volume, and temperature.

Metric to Imperial Conversion Chart
Convert	To	Multiply by
Kilometers	Miles	0.62
Kilometers	Feet	3280.8
Meters	Feet	3.28
Centimeters	Inches	0.39
Millimeters	Inches	0.039
Liters	Quarts	1.057
Liters	Gallons	0.264
Milliliters	Cups	0.0042
Milliliters	Ounces	0.0338
Celsius	Fahrenheit	°C x 9/5 + 32 = °F
Kilogram	Tons	0.0011
Kilogram	Pounds	2.2046
Grams	Ounces	0.035
Grams	Pounds	0.002205
Milligrams	Ounces	0.000035

Imperial to Metric Conversion Chart
Convert	To	Multiply by
Fahrenheit	Celsius	(°F - 32) x 5/9 = °C
Inches	Meters	0.0254
Inches	Centimeters	2.54
Inches	Millimeters	25.40
Feet	Meters	0.30
Yards	Meters	0.91
Yards	Kilometers	0.00091
Miles	Kilometers	1.61
Ounces	Milliliters	29.57
Cups	Milliliters	236.6
Quarts	Liters	0.95
Gallons	Liters	3.785
Ounces	Milligrams	28350
Ounces	Grams	28.35
Pounds	Kilograms	0.454
Tons	Kilograms	907.18

Convert Length: Inch, Foot, Yard
Convert Imperial to Metric Area: Inches, Feet, Acres
1 inch = 2.54 centimeters 1 inch = 25.4 millimetres 1 foot = 0.3048 meters 1 foot = 30.48 centimetres 1 foot = 12 inches 1 yard = 0.9144 meters 1 yard = 91,44 cm 1 yard = 3 feet 1 yard = 0.000568181818 miles
1 square inch = 6.452 square cm 1 square foot = 929.0304 square cm 1 square yard = 8361.2736 square cm 1 square yard = 9 square feet 1 acres = 0.404685642 hectares 1 square mile = 2.59 km
Distance: Miles
1 mile = 1.609344 kilometers 1 mile = 1,760 yards
Volume: Liter
1 liter = 1.0566882 US quarts 1 liter = 10 deciliters 1 liter = 100 centiliters 1 liter = 0.264172051 US gallons
Convert Imperial to Metric Speed: MPH
1 mile per hour = 1.609344 kilometers per hour
Temperature: Fahrenheit
(Fahrenheit - 32) x 0.55 = Celsius
Volume: Cup, Pint, Quart, Gallon
1 pint = 2 cups 1 quart = 8 pints 1 US quart = 0.94635295 liters 1 gallon = 4 quarts 1 US gallon = 3.7854118 liters
Weight: Gram, Dram, Kilogram
1 gram = 0.0352739619 ounce 1 dram = 0.0625 ounce 1 gram = 0.564383391 drams 1 dram = 1.7718452 grams 1 kilogram = 2.20462262 pounds 1 gram = 1000 milligrams 1 kilogram = 0.00110231131 US tons
Weight: Ounces, Pounds, Tons
1 ounce = 28.3495231 grams 1 ounce = 16 drams 1 ounce = 0.0625 pounds 1 pound = 16 ounces 1 pound = 0.45359237 kilograms 1 grain = 64.79891 milligram 1 US ton = 907.18474 kilograms
Distance: Kilometers
1 kilometer = 0.621371192 miles 1 kilometer = 1000 meters
Length: Centimeter, Meter
1 centimeter = 0.393700787 in. 1 centimeter = 0.01 meters 1 meter = 3.2808399 feet 1 meter = 1.0936133 yards 1 meter = 0.001 kilometers 1 meter = 100 centimeters
Convert Metric to Imperial Speed: KPH
1 kilometer per hour = 0.621371192 miles per hour
Temperature: Celsius
(Celsius x 1.8) + 32 = Fahrenheit
Convert Metric to Imperial Area: Centimeters, Hectares
1 sq. cm = 0.15500031 sq. in. 1 sq. cm = 0.00107639104 sq. ft 1 sq. cm = 0.000119599005 sq. yrds. 1 hectares = 2.47105381 acres

Hard and Soft Measurement Conversions

Hard Conversions

A hard conversion (adaptive conversion) may not be exactly equivalent. A hard conversion changes the measurement to numbers and units in the new system that are easier to work with. Nominal values are sometimes allowed and used, and a hard conversion sometimes involves a slightly different substitution configuration, or measurement, of the item in question.

Soft Conversions

Some conversion measurements from a system of units to another needs to be exact - this means there is no increasing - or decreasing - the precision of the first measurement unit. This is called soft conversion. Soft conversion does not involve changing the actual physical configuration of the thing that is being measured.

Insights, Analysis, and Developments

Editorial Note: In a world where daily tasks, recipes, and medical instructions often cross between metric and imperial systems, having a reliable, clearly explained set of conversion formulas is more than a convenience-it's a necessity. This article stands out for its practical focus and accessibility, ensuring that people of all backgrounds, including those with disabilities or limited technical expertise, can confidently navigate measurement differences without confusion or error - Disabled World (DW).

Author Credentials: Ian is the founder and Editor-in-Chief of Disabled World, a leading resource for news and information on disability issues. With a global perspective shaped by years of travel and lived experience, Ian is a committed proponent of the Social Model of Disability-a transformative framework developed by disabled activists in the 1970s that emphasizes dismantling societal barriers rather than focusing solely on individual impairments. His work reflects a deep commitment to disability rights, accessibility, and social inclusion. To learn more about Ian's background, expertise, and accomplishments, visit his full biography.