To use the calculator, place your cursor in the desired unit field and write a number.The calculator will automatically convert your number and display the result in the other unit fields. If needed use the dot "." as the decimal separator.
Use the overview below to better understand the meaning and history of the different weight units.

Light Speed (299,792,500m/s)
The speed of light in vacuum, commonly denoted c, is a universal physical constant important in many areas of physics. Its exact value is 299,792,458 metres per second (approximately 300,000 km/s (186,000 mi/s)). It is exact because by international agreement a metre is defined to be the length of the path travelled by light in vacuum during a time interval of 1/299792458 second. According to special relativity, c is the maximum speed at which all conventional matter and hence all known forms of information in the universe can travel. Though this speed is most commonly associated with light, it is in fact the speed at which all massless particles and changes of the associated fields travel in vacuum (including electromagnetic radiation and gravitational waves). Such particles and waves travel at c regardless of the motion of the source or the inertial reference frame of the observer. In the special and general theories of relativity, c interrelates space and time, and also appears in the famous equation of mass–energy equivalence E = mc2.

Mile per second (1,609.344m/s)
The mile per second is a unit of speed, expressing the number of miles travelled in one second.

Kilometer per second (1,000m/s)
The kilometre per second (American English: kilometer per second) is a unit of speed, expressing the number of kilometres travelled in one second.

Mach (340.2900m/s)
In fluid dynamics, the Mach number (M or Ma) is a dimensionless quantity representing the ratio of flow velocity past a boundary to the local speed of sound. By definition, at Mach 1, the local flow velocity u is equal to the speed of sound. At Mach 0.65, u is 65% of the speed of sound (subsonic), and, at Mach 1.35, u is 35% faster than the speed of sound (supersonic).

Mile per minute (26.8224m/s)
The mile per minute is a unit of speed, expressing the number of miles travelled in one minute.

Kilometer per minute (16.66667m/s)
The kilometre per minute (American English: kilometer per minute) is a unit of speed, expressing the number of kilometres travelled in one minute.

Meters per second (1m/s)
Metre per second (American English: meter per second) is an SI derived unit of both speed (scalar) and velocity (vector quantity which specifies both magnitude and a specific direction), defined by distance in metres divided by time in seconds.

Yard per second (0.9144000m/s)
The yard per second is a unit of speed, expressing the number of yards travelled in one second.

Knot (0.5144444m/s)
The knot is a unit of speed equal to one nautical mile per hour, exactly 1.852 km/h (approximately 1.15078 mph). The ISO standard symbol for the knot is kn. The same symbol is preferred by the Institute of Electrical and Electronics Engineers (IEEE); kt is also common. The knot is a nonSI unit. Worldwide, the knot is used in meteorology, and in maritime and air navigation—for example, a vessel travelling at 1 knot along a meridian travels approximately one minute of geographic latitude in one hour.

Mile per hour (0.4470400m/s)
Miles per hour (abbreviated mph, MPH or mi/h) is an imperial and United States customary unit of speed expressing the number of statute miles covered in one hour.

Foot per second (0.3048000m/s)
The foot per second (plural feet per second) is a unit of both speed (scalar) and velocity (vector quantity, which includes direction). It expresses the distance in feet (ft) traveled or displaced, divided by the time in seconds (s, or sec). The corresponding unit in the International System of Units (SI) is the metre per second. Abbreviations include ft/s, ft/sec and fps, and the scientific notation ft s⁻¹.

Kilometer per hour (0.2777778m/s)
The kilometre per hour (American English: kilometer per hour) is a unit of speed, expressing the number of kilometres travelled in one hour. Worldwide, km/h is the most commonly used unit of speed on road signs and car speedometers.

Inch per second (0.02540000m/s)
The inch per second is a unit of speed or velocity. It expresses the distance in inches (in) traveled or displaced, divided by time in seconds (s, or sec). The equivalent SI unit is the metre per second. Abbreviations include in/s, in/sec, ips, and less frequently in s⁻¹.

Mile per day (0.01862667m/s)
The mile per day is a unit of speed, expressing the number of miles travelled in one day.

Meter per minute (0.01666667m/s)
Metre per minute (American English: meter per minute) is an SI derived unit of both speed (scalar) and velocity (vector quantity which specifies both magnitude and a specific direction), defined by distance in metres divided by time in minutes.

Yard per minute (0.01524m/s)
The yard per minute is a unit of speed, expressing the number of yards travelled in one minute.

Kilometer per day (0.01157407m/s)
The kilometre per day (American English: kilometer per day) is a unit of speed, expressing the number of kilometres travelled in one day.

Centimeter per second (0.01m/s)
A centimetre (international spelling as used by the International Bureau of Weights and Measures; symbol cm) or centimeter (American spelling) per second is a unit of speed, expressing the number of centimeters travelled in one second.

Foot per minute (0.00508m/s)
The feet per minute is a unit of speed, expressing the number of feet travelled in one minute.

Millimeter per second (0.001m/s)
The millimetre (International spelling as used by the International Bureau of Weights and Measures; SI unit symbol mm) or millimeter (American spelling) per second is a unit of speed, expressing the number of millimeters travelled in one second.

Inch per minute (0.0004233333m/s)
The inch per minute is a unit of speed, expressing the number of inches travelled in one minute.

Meter per hour (0.0002777778m/s)
Metre per hour (American spelling: meter per hour) is a metric unit of both speed (scalar) and velocity (Vector  Geometry). Its symbol is m/h or m·h⁻¹ (not to be confused with the imperial unit symbol mph. By definition, an object travelling at a speed of 1 m/h for an hour would move 1 metre). The term is rarely used however as the units of metres per second and kilometres per hour are considered sufficient for the majority of circumstances. Metres per hour can however be convenient for documenting extremely slow moving objects. A Garden Snail for instance, typically moves at a speed of up to 47 metres per hour.

Yard per hour (0.000254m/s)
The yard per hour is a unit of speed, expressing the number of yards travelled in one hour.

Centimeter per minute (0.0001666667m/s)
A centimetre (international spelling as used by the International Bureau of Weights and Measures; symbol cm) or centimeter (American spelling) per minute is a unit of speed, expressing the number of centimeters travelled in one minute.

Foot per hour (0.00008466667m/s)
The feet per hour is a unit of speed, expressing the number of feet travelled in one hour.

Millimeter per minute (0.00001666667m/s)
The millimetre (International spelling as used by the International Bureau of Weights and Measures; SI unit symbol mm) or millimeter (American spelling) per minute is a unit of speed, expressing the number of millimeters travelled in one minute.

Meter per day (0.00001157407m/s)
Metre per day (American English: meter per day) is an SI derived unit of both speed (scalar) and velocity (vector quantity which specifies both magnitude and a specific direction), defined by distance in metres divided by time in day.

Yard per day (0.00001058333m/s)
The yard per day is a unit of speed, expressing the number of yards travelled in one day.

Inch per hour (0.000007055556m/s)
The inch per hour is a unit of speed, expressing the number of inches travelled in one hour.

Foot per day (0.000003527778m/s)
The feet per day is a unit of speed, expressing the number of feet travelled in one day.

Centimeter per hour (0.000002777778m/s)
A centimetre (international spelling as used by the International Bureau of Weights and Measures; symbol cm) or centimeter (American spelling) per hour is a unit of speed, expressing the number of centimeters travelled in one hour.

Micron per second (0.000001m/s)
The micrometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron per second is a unit of speed, expressing the number of microns travelled in one second.

Inch per day (0.0000002939815m/s)
The inch per day is a unit of speed, expressing the number of inches travelled in one day.

Millimeter per hour (0.0000002777778m/s)
The millimetre (International spelling as used by the International Bureau of Weights and Measures; SI unit symbol mm) or millimeter (American spelling) per hour is a unit of speed, expressing the number of millimeters travelled in one hour.

Centimeter per day (0.0000001157407m/s)
A centimetre (international spelling as used by the International Bureau of Weights and Measures; symbol cm) or centimeter (American spelling) per day is a unit of speed, expressing the number of centimeters travelled in one day.

Micron per minute (0.00000001666667m/s)
The micrometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron per minute is a unit of speed, expressing the number of microns travelled in one minute.

Millimeter per day (0.00000001157407m/s)
The millimetre (International spelling as used by the International Bureau of Weights and Measures; SI unit symbol mm) or millimeter (American spelling) per day is a unit of speed, expressing the number of millimeters travelled in one day.

Micron per hour (0.0000000002777778m/s)
The micrometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron per hour is a unit of speed, expressing the number of microns travelled in one hour.

Micron per day (0.00000000001157407m/s)
The micrometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron per day is a unit of speed, expressing the number of microns travelled in one day.