Metric Converter – Online Conversion

(Pound to Kg, Km to Mile, Litre/Liter to Gallon and more)

Do not know how to convert metrics? Our Metric Converter provides easy to use and convenient metric conversions for over many various units and measurements, including weight, length, volume.

To do your metric conversion go to the conversion page for your measure (e.g. weight, volume or length), type your value in the box near the unit you are conversing from (e.g. foot) and our converter will make the metric conversations automatically.

The value you have typed gets instantly converted to all other possible units!

Metric Conversion Examples

Litre / Liter to Gallon

A litre is defined as a special name for a cubic decimetre (1 L ≡ 1 dm³). Hence 1 L ≡ 0.001 m³ ≡ 1000 cm³, and 1000 L ≡ 1 m³ (exactly).

The imperial (UK) gallon was legally defined as 4.54609 litres. This definition is used in some Commonwealth countries and Ireland, and is based on the volume of 10 pounds of water at 62 °F. (A US liquid gallon of water weighs about 8.33 pounds at the same temperature.) The imperial fluid ounce is defined as 1⁄160 of an imperial gallon. On 1 January 2000, it ceased to be a legal unit of measure within the United Kingdom for economic, health, safety or administrative purposes.

The US liquid gallon is legally defined as 231 cubic inches, and is equal to exactly 3.785411784 litres or about 0.133680555 cubic feet. This is the most common definition of a gallon in the United States. The US fluid ounce is defined as 1⁄128 of a US gallon.

The US dry gallon is one-eighth of a US Winchester bushel of 2150.42 cubic inches, thus it is equal to exactly 268.8025 cubic inches or 4.40488377086 litres. The US dry gallon is less commonly used, and is not listed in the relevant statute, which jumps from the dry quart to the peck.

Liter to Gallon: 1 U.S. gallon is 3.78541178 liters.

Km to Mile

The kilometre (American spelling: kilometer), symbol km is a unit of length in the metric system, equal to one thousand metres and is therefore exactly equal to the distance travelled by light in free space in 1⁄299 792.458 of a second. It is the conventionally used measurement unit for expressing distances between geographical places in most of the world; notable exceptions are the United States and the United Kingdom where the statute mile is used.

A mile is a unit of length in a number of different systems. In contemporary English, a mile most commonly refers to the statute mile of 5,280 feet (1,760 yards, or 1,609.344 metres), the survey mile of 5,280 survey feet (1,609.3472 metres (5,280.01 ft)) or the nautical mile of 1,852 metres (6,076.12 ft). It is about a third of the old measurement, the league. The use of statute miles as a unit of measurement is largely used in the United States and the United Kingdom. There are many other historical miles and similar units in other systems translated as miles in English, varying between one and fifteen kilometres.

Km to gallon: One kilometer is equivalent to 0.62 miles.

Pound to Kg

A number of different definitions of the pound have been used in Britain. Amongst these are the avoirdupois pound and the obsolete tower, merchant's and London pounds. The weight of precious metals when given in pounds and/or ounces usually assumes Troy pounds and ounces; these units are not otherwise used today. Historically the pound sterling was a Tower pound of silver. In 1528 the standard was changed to the Troy pound.

The kilogram (symbol: kg) is the base unit of mass in the International System of Units (SI, from the French Le Système International d’Unités), which is the modern standard governing the metric system. The kilogram is defined as being equal to the mass of the International Prototype Kg (IPK), which is almost exactly equal to the mass of one liter of water. It is the only SI base unit with an SI prefix as part of its name. It is also the only SI unit that is still defined by an artifact rather than a fundamental physical property that can be reproduced in different laboratories.

Pound to Kg: One kilogram is equivalent to 2.2 pounds

History – Weights and Measures

The metric system was devised in France in the 18th century. The goal was to replace the chaotic collection of units being in use with a system based on one standard and decimal factors.

The standard for length was created by dividing the quarter of the Earth diameter by ten millions. The resulting length was named meter. The definition of meter changed several times since to make it more precise. The latest and the most precise definition of meter is "the distance light travels in a vacuum in 1/299,792,458 second". The standards for other measurements in metric system were set in a similar way.

The metric system or International System of Units (SI) is based on seven base units for seven base quantities that are mutually independent. The quantites are: length (meter), mass (kilogram), time (second), electric current (ampere), thermodynamic temperature (kelvin), amount of substance (mole) and luminous intensity (candela). All other units are derived from the base ones.

All units of a particular measurement are consctructed from the corresponding base unit by adding some metric prefix. The table of metric prefixes useful for metric conversions is provided below.

Metric Prefixes

Metric prefixes are pretty easy to understand and very handy for metric conversions (conversion tables). You don't have to know the nature of a unit to convert, for example, from kilo-unit to mega-unit. All metric prefixes are powers of 10. The most commonly used prefixes are highlighted in the table.

Prexis	Symbol	Factor
yotta	Y	1,000,000,000,000,000,000,000,000
zetta	Z	1,000,000,000,000,000,000,000
exa	E	1,000,000,000,000,000,000
peta	P	1,000,000,000,000,000
tera	T	1,000,000,000,000
giga	G	1,000,000,000
mega	M	1,000,000
kilo	k	1,000
hecto	h	100
deka	da	10
deci	d	0.1
centi	c	0.01
milli	m	0.001
micro	µ	0.000,001
nano	n	0.000,000,001
pico	p	0,000,000,000,001
femto	f	0.000,000,000,000,001
atto	a	0.000,000,000,000,000,001
zepto	z	0.000,000,000,000,000,000,001
yocto	y	0.000,000,000,000,000,000,000,001

Most people even in the countries where metric system is used only know the most important metric prefixes like 'kilo' and 'milli'. They are very handy for understanding metric conversions. The prefixes like 'zepto' or 'yotta' are very specific and used mostly in measurement conversions.

The Avoirdupois system is a system of weights (or, properly, mass) based on a pound of sixteen ounces. It is the everyday system of weight used in the United States, and is still widely used to varying degrees by many people in Canada, the United Kingdom, and some other former British colonies despite the official adoption of the metric system

The International System of Units (abbreviated SI from the French Le Système International d'Unités) is the modern form of the metric system and is generally a system of units of measurement devised around seven base units and the convenience of the number ten. It is the world's most widely used system of measurement, both in everyday commerce and in science.

The older metric system included several groups of units. The SI was developed in 1960 from the old metre-kilogram-second system, rather than the centimetre-gram-second system, which, in turn, had a few variants. Because the SI is not static, units are created and definitions are modified through international agreement among many nations as the technology of measurement progresses, and as the precision of measurements improves.

The system has been nearly globally adopted. Three principal exceptions are Burma (Myanmar), Liberia, and the United States. The United Kingdom has officially adopted the International System of Units but not with the intention of replacing customary measures entirely.