Conversion Glossary
A comprehensive reference of measurement terms and conversion concepts.
A
Area
A measure of the size of a surface. It is calculated by multiplying length by width. Common units include square feet, square meters, and acres.
Try the Square Meters to Square Feet ConverterAcre
A unit of area commonly used in the US and UK. One acre equals 43,560 square feet or approximately 4,047 square meters.
Try the Acres to Square Feet ConverterAbsolute Zero
The lowest possible temperature, equal to 0 Kelvin, −273.15°C, or −459.67°F. At this temperature, molecular motion theoretically stops.
Try the Kelvin to Celsius ConverterAtmosphere
A unit of pressure equal to the standard atmospheric pressure at sea level: approximately 101,325 Pascals, 14.696 PSI, or 1.01325 bar.
Amp
Short for Ampere, the SI unit of electric current. Measures the flow of electric charge. Named after André-Marie Ampère. Phone chargers typically use 1–3 amps.
Accuracy
How close a measurement is to the true or accepted value. Accurate measurements hit the target; precise measurements are repeatable but may still be off-target.
Approximation
A value that is close to but not exactly equal to the true value. Many conversions (especially between metric and imperial) involve approximations.
B
Body Temperature
Normal human body temperature is approximately 37°C (98.6°F) or 310.15 K. It can vary slightly by individual and time of day.
Try the Celsius to Fahrenheit ConverterBoiling Point
The temperature at which a liquid turns to vapor. Water boils at 100°C (212°F) at standard atmospheric pressure (sea level).
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A metric unit of pressure equal to 100,000 Pascals or approximately 14.504 PSI. Commonly used in meteorology and diving.
BTU
British Thermal Unit. The energy required to raise one pound of water by 1°F. Used in HVAC and energy industries. 1 BTU ≈ 1,055 joules.
Bit
The smallest unit of data in computing. A bit can hold a value of either 0 or 1 (binary). All digital data is made up of bits.
Byte
A unit of digital data equal to 8 bits. A single byte can represent 256 different values (0–255) and is often used to store one character of text.
Bandwidth
The maximum rate of data transfer across a network connection. Measured in bits per second (bps), megabits per second (Mbps), or gigabits per second (Gbps).
Baking Conversion
Converting measurements in baking recipes between volume (cups/tablespoons) and weight (grams/ounces). Weight measurements are more precise for baking.
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The first currency in a currency pair. In EUR/USD, the euro is the base currency. The exchange rate tells you how much of the quote currency one unit of base currency buys.
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The difference between the price a buyer will pay (bid) and the price a seller will accept (ask) for a currency. Banks and exchanges profit from this spread.
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A fundamental unit in a measurement system from which other units are derived. SI base units include the meter (length), kilogram (mass), and second (time).
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A prefix used in computing that scales by powers of 2. Kibi (KiB = 1,024 bytes), mebi (MiB = 1,048,576 bytes), gibi (GiB), tebi (TiB). These differ from the decimal kilo/mega/giga prefixes.
C
Conversion Factor
A numerical value used to change one set of units to another, by multiplying or dividing. For example, the conversion factor from inches to centimeters is 2.54.
Try the Inches to CM ConverterCelsius
A temperature scale where 0° is the freezing point of water and 100° is the boiling point at standard atmospheric pressure. Also known as Centigrade.
Try the Celsius to Fahrenheit ConverterCentimeter
A metric unit of length equal to 1/100 of a meter or approximately 0.394 inches.
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The process of changing one currency into another using the current exchange rate. Rates change constantly and may include fees.
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A unit of mass used for gemstones equal to 0.2 grams. Also used to describe the purity of gold, measured in parts per 24.
Try the Grams to Ounces ConverterCubic Meter
The SI unit of volume equal to a cube with sides of one meter. One cubic meter equals 1,000 liters.
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A US customary unit of volume equal to 8 fluid ounces or approximately 236.6 milliliters. A standard measurement in cooking and baking.
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A metric unit of volume equal to 1 milliliter. Often used in medicine (e.g., a 10 cc syringe holds 10 mL). Abbreviated as cc or cm³.
Try the ML to Fluid Ounces ConverterCubic Inch
An imperial unit of volume equal to the volume of a cube with sides one inch long. One cubic inch equals approximately 16.39 milliliters.
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A period of 100 years. Used in historical timelines and long-term measurements.
Calorie
A unit of energy. The small calorie (cal) is the energy to raise 1 gram of water by 1°C. The food calorie (Cal or kcal) equals 1,000 small calories.
Current
The flow of electric charge through a conductor, measured in amperes (A). Direct current (DC) flows in one direction; alternating current (AC) reverses direction periodically.
Calibration
The process of adjusting or verifying a measuring instrument against a known standard to ensure it gives accurate readings.
Coefficient
A numerical multiplier in a formula. In conversions, the coefficient is the fixed factor used to change one unit into another, such as 2.54 for inches to centimeters.
D
Decimeter
A metric unit of length equal to 1/10 of a meter or 10 centimeters. Less commonly used in everyday life.
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The numerical measurement of how far apart two points are. Length and distance are closely related; distance often refers to the space between two locations.
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A unit of time equal to 24 hours or 86,400 seconds. Based on the period it takes Earth to rotate once on its axis.
Decade
A period of 10 years. The word comes from the Greek 'dekas' meaning a group of ten.
Data Transfer Rate
The speed at which data is transmitted from one place to another, typically expressed in Mbps or Gbps. Determines how fast files upload or download.
Dry Measurement
Measuring ingredients like flour, sugar, and spices by volume using measuring cups or spoons, or by weight on a kitchen scale. Dry and liquid cups hold the same volume.
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A number expressed in base 10, using a decimal point. For example, 3.14 or 0.5. The metric system is based on decimal multiples (10, 100, 1,000, etc.).
Derived Unit
A unit formed by combining base units. For example, speed (m/s) is derived from meters and seconds; area (m²) is derived from meters.
Try the Square Meters to Square Feet ConverterDimensional Analysis
A method of solving conversion problems by multiplying by fractions that equal 1 (e.g., 1 inch/2.54 cm). Ensures units cancel correctly.
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A unit of angle equal to 1/360 of a full circle. The degree is the everyday unit for measuring angles, with a right angle equal to 90°.
Density
Mass per unit volume, often written ρ (rho). The SI unit is kg/m³. Water has a density of about 1,000 kg/m³ (or 1 g/cm³). Density determines whether objects float or sink.
E
Exchange Rate
The value of one currency expressed in terms of another. Exchange rates fluctuate based on economic factors and market conditions.
Try the USD to EUR ConverterElectronvolt
A unit of energy used in atomic and nuclear physics. Equal to the energy gained by an electron moving through 1 volt. 1 eV = 1.602 × 10⁻¹⁹ joules.
Energy
The capacity to do work or produce heat. It comes in many forms including kinetic, potential, thermal, electrical, and chemical. SI unit is the joule.
Exabyte
A unit of digital data equal to 1,000 petabytes (10¹⁸ bytes). Used to describe global internet data volumes. The world generates multiple exabytes of data per day.
Exponent
A number indicating how many times the base is multiplied by itself. In 10³ = 1,000, the exponent is 3. Used in scientific notation and orders of magnitude.
F
Fahrenheit
A temperature scale where 32° is the freezing point of water and 212° is the boiling point. Primarily used in the United States.
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An imperial unit of length equal to 12 inches or approximately 0.3048 meters. Plural: feet.
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An imperial unit of length equal to 1/8 of a mile or 220 yards (about 201 meters). Commonly used in horse racing.
Try the Yards to Meters ConverterFluid Ounce
A unit of volume for liquids. One US fluid ounce equals approximately 29.57 milliliters. Different from the weight ounce.
Try the Fluid Ounces to ML ConverterFreezing Point
The temperature at which a liquid solidifies. Water freezes at 0°C (32°F) at standard atmospheric pressure.
Try the Fahrenheit to Celsius ConverterFuel Economy
The efficiency of a vehicle expressed as the distance traveled per unit of fuel. Common measures include MPG (US/UK), L/100km (Europe), and km/L (Asia).
Forex
Foreign Exchange market — the global marketplace where currencies are traded. It is the largest financial market in the world, with over $7 trillion traded daily.
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How often a repeating event occurs per unit of time, measured in hertz. A higher frequency means more cycles per second. Sound, light, radio, and processor speeds are all described by frequency.
Force
A push or pull that can change an object's motion. Measured in newtons (SI) or pound-force (imperial). Force equals mass times acceleration (F = ma).
Fuel
A substance that releases energy when burned or reacted. In vehicle fuel-economy conversions, the amount of fuel (gallons or liters) is compared to the distance traveled.
G
Gallon
A unit of volume. One US gallon equals approximately 3.785 liters. One Imperial gallon equals approximately 4.546 liters.
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A metric unit of mass equal to 1/1,000 of a kilogram or approximately 0.035 ounces.
Try the Grams to Ounces ConverterGigawatt
A unit of power equal to one billion watts or 1,000 megawatts. Often used in discussions of national electricity grids and large-scale solar/wind farms.
Gigabyte
A unit of digital data equal to 1,000 megabytes (SI) or 1,024 MB (binary). Abbreviated GB. Smartphone storage is typically measured in gigabytes.
Gbps
Gigabits per second. Used for high-speed networking and fiber optic connections. 1 Gbps = 1,000 Mbps or 125 megabytes per second.
Gauge
A measuring instrument or a standard of measurement. In manufacturing, gauges measure wire thickness, sheet metal thickness, pipe diameters, and more.
Try the Inches to CM ConverterGradian
A unit of angle, also called a gon, equal to 1/400 of a full circle. A right angle is 100 gradians. Used mainly in surveying and some European engineering contexts.
Gigahertz
A unit of frequency equal to one billion hertz. Abbreviated GHz. Modern computer processors run at several GHz, and Wi-Fi operates at 2.4 or 5 GHz.
Gibibyte
A unit of digital data equal to exactly 1,073,741,824 bytes (1,024 MiB). Abbreviated GiB. A '500 GB' drive holds about 465 GiB, which is why it shows less space in an operating system.
H
Hectare
A metric unit of area equal to 10,000 square meters or approximately 2.471 acres. Commonly used in agriculture and land surveying.
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A unit of time equal to 60 minutes or 3,600 seconds. There are 24 hours in one day.
Horsepower
A unit of power originally defined to compare engine output to the work a horse can do. 1 mechanical horsepower ≈ 745.7 watts.
Hertz
The SI unit of frequency, equal to one cycle per second. Named after Heinrich Hertz. Abbreviated Hz. One kilohertz (kHz) is 1,000 Hz, one megahertz (MHz) is 1 million Hz.
I
Imperial System
A system of weights and measures originally developed in England. Includes units like inches, feet, pounds, and gallons.
Try the Inches to CM ConverterInch
An imperial unit of length equal to 1/12 of a foot or exactly 2.54 centimeters.
Try the Inches to CM ConverterIngredient Scaling
Adjusting the amount of each ingredient in a recipe proportionally to make a larger or smaller batch while maintaining the same flavor and texture.
Try the Cups to Tablespoons ConverterInverse Relationship
A relationship where one value increases as the other decreases. MPG and L/100km are inversely related: doubling MPG halves L/100km. Such conversions use division, not multiplication.
J
Joule
The SI unit of energy. One joule equals the work done when a force of one Newton moves an object one meter. Named after James Prescott Joule.
K
Kelvin
The SI base unit of temperature. 0 Kelvin is absolute zero (-273.15°C). Unlike Celsius and Fahrenheit, Kelvin does not use degrees.
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A metric unit of length equal to 1,000 meters or approximately 0.621 miles.
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The SI base unit of mass. One kilogram is approximately 2.205 pounds.
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Kilometers per hour. The most widely used unit of speed globally. 1 km/h equals approximately 0.621 mph or 0.278 meters per second.
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A unit of speed used in maritime and aviation contexts equal to one nautical mile per hour (1.852 km/h or approximately 1.151 mph).
Try the KM to Miles ConverterKilopascal
A unit of pressure equal to 1,000 Pascals. Used in meteorology, tire inflation, and engineering. Standard atmosphere ≈ 101.3 kPa.
Kilojoule
A unit of energy equal to 1,000 joules. Used in food nutrition labeling in many countries (e.g., 1 kcal ≈ 4.184 kJ).
Kilocalorie
Equal to 1,000 calories. The unit used on food labels (often written simply as 'Calories' with a capital C). 1 kcal ≈ 4.184 kJ.
Kilowatt-Hour
A unit of energy equal to 1 kilowatt of power sustained for 1 hour. Used by electric utilities to measure electricity consumption. 1 kWh = 3,600,000 joules.
Kilowatt
A unit of power equal to 1,000 watts. Commonly used to rate electrical appliances, generators, and EV charging speeds.
Kilobyte
A unit of digital data equal to 1,000 bytes (SI) or 1,024 bytes (binary/IEC). Abbreviated KB. Small text files are typically measured in kilobytes.
Kbps
Kilobits per second. A unit of data transfer rate equal to 1,000 bits per second. Used for slower connections, audio streaming, and modem speeds.
KM/L
Kilometers per liter. A fuel economy metric used in many countries. 1 km/L ≈ 2.352 MPG. Higher values indicate better fuel efficiency.
Try the KM to Miles ConverterkWh (Electrical)
Kilowatt-hour — the standard unit used by electric utilities to bill electricity consumption. 1 kWh means using 1,000 watts continuously for one hour.
Kilohertz
A unit of frequency equal to 1,000 hertz. Abbreviated kHz. Used for audio frequencies and AM radio.
Kilogram-Force
A unit of force equal to the weight of a one-kilogram mass under standard gravity (9.80665 N). Abbreviated kgf. Largely replaced by the newton in scientific work.
Kibibyte
A unit of digital data equal to exactly 1,024 bytes. Abbreviated KiB. It is the binary-system counterpart of the decimal kilobyte (1,000 bytes).
L
Length
A measure of distance. In the metric system, the base unit is the meter. In the imperial system, common units include inches, feet, yards, and miles.
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A metric unit of volume equal to 1,000 cubic centimeters or approximately 0.264 US gallons.
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A historical unit of distance roughly equal to 3 miles (about 4.8 km). Still referenced in literature and some geographic names.
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A unit of weight used in the UK equal to 2,240 pounds or approximately 1,016 kilograms. Also called an imperial ton.
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The time delay between a data request and the response. Measured in milliseconds (ms). Lower latency means a more responsive connection.
L/100km
Liters per 100 kilometers. The fuel economy standard used in Europe and Canada. Lower values mean better efficiency. 30 MPG ≈ 7.84 L/100km.
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Measuring liquid ingredients (water, milk, oil) by volume, typically in fluid ounces, cups, or milliliters. A liquid measuring cup has a spout for easy pouring.
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Metric System
An international decimalized system of measurement, based on the meter, kilogram, and second. Used by most countries worldwide.
Mass
A measure of the amount of matter in an object. While often used interchangeably with weight, mass is not affected by gravity.
Try the KG to Pounds ConverterMile
An imperial unit of length equal to 5,280 feet or approximately 1.609 kilometers.
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The base unit of length in the metric system. One meter equals 100 centimeters, 1,000 millimeters, or approximately 3.281 feet.
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A metric unit of length equal to 1/1,000 of a meter or approximately 0.039 inches. Commonly used in engineering and manufacturing.
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A metric unit of length equal to one millionth of a meter (0.000001 m). Used in science and engineering to measure very small distances.
Milligram
A metric unit of mass equal to 1/1,000 of a gram. Used in medicine and science where very small quantities are measured.
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A unit of mass equal to 1,000 kilograms or approximately 2,204.6 pounds. Also called a tonne. Used in international shipping and trade.
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A metric unit of mass equal to one millionth of a gram (0.000001 g). Used in pharmaceutical dosing and laboratory science.
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A metric unit of volume equal to 1/1,000 of a liter or one cubic centimeter (1 cm³). Commonly used for liquid medicines and recipes.
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Miles per hour. A unit of speed commonly used in the US and UK. 1 mph equals approximately 1.609 km/h or 0.447 meters per second.
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The SI unit of speed, abbreviated m/s. Used in science and engineering. 1 m/s equals 3.6 km/h or approximately 2.237 mph.
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A dimensionless unit expressing speed relative to the speed of sound. Mach 1 ≈ 343 m/s (1,235 km/h) at sea level in standard conditions.
Minute
A unit of time equal to 60 seconds. There are 60 minutes in one hour.
Month
A unit of time approximately equal to 30 or 31 days (28–29 for February). There are 12 months in a year, totaling approximately 365.25 days.
Millisecond
A unit of time equal to 1/1,000 of a second. Used in computing, sports timing, and scientific measurements.
Microsecond
A unit of time equal to one millionth of a second. Used in electronics and telecommunications to measure signal processing speeds.
Millibar
A unit of pressure equal to 1/1,000 of a bar or 100 Pascals. Widely used in meteorology to measure atmospheric pressure.
Megawatt
A unit of power equal to 1,000,000 watts or 1,000 kilowatts. Used to measure the output of power plants and large industrial systems.
Megabyte
A unit of digital data equal to 1,000 kilobytes (SI) or 1,024 KB (binary). Abbreviated MB. Photos and short audio clips are typically megabytes in size.
Mbps
Megabits per second. A common unit for measuring internet connection speeds. Note: 1 Mbps = 0.125 MB/s, so a 100 Mbps connection transfers ~12.5 MB per second.
MPG
Miles per gallon. A measure of fuel efficiency used in the US and UK. Higher MPG means the vehicle travels more miles per gallon of fuel.
Try the Miles to KM ConverterMegahertz
A unit of frequency equal to one million hertz. Abbreviated MHz. Used for FM radio, older computer processors, and many wireless signals.
Metric Prefix
A prefix added to a unit to indicate a multiple or fraction. Common prefixes: kilo (×1,000), centi (÷100), milli (÷1,000), micro (÷1,000,000), mega (×1,000,000), giga (×1,000,000,000), tera (×1,000,000,000,000).
Mebibyte
A unit of digital data equal to exactly 1,048,576 bytes (1,024 KiB). Abbreviated MiB. Operating systems often display file sizes in mebibytes but label them 'MB'.
Magnitude
The size or extent of a quantity. Orders of magnitude describe how many powers of 10 separate two values; a number 10 times larger is one order of magnitude greater.
Measurement Standard
An officially agreed reference that defines a unit. The meter is defined by the distance light travels in a vacuum in 1/299,792,458 of a second, ensuring all measurements trace back to a constant of nature.
N
Nautical Mile
A unit of length used in navigation equal to exactly 1,852 meters (about 1.151 statute miles). Based on one minute of arc of latitude.
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A metric unit of length equal to one billionth of a meter. Used in physics and chemistry to measure wavelengths of light and atomic structures.
Nanosecond
A unit of time equal to one billionth of a second. Used in computing to measure processor speeds and memory access times.
Newton
The SI unit of force. One newton is the force needed to accelerate a 1 kg mass at 1 m/s². Named after Isaac Newton. Abbreviated N. A small apple weighs about 1 newton.
Newton-Meter
The SI unit of torque, abbreviated Nm. One Nm is the torque from a 1 newton force applied at a 1 meter distance. Also a unit of energy equivalent to one joule, but torque and energy contexts are kept separate.
Nautical Unit
Measurement units used in sea and air navigation, based on the nautical mile (1,852 m) and the knot (one nautical mile per hour). These units relate directly to the Earth's coordinates.
O
Ounce
An imperial unit of weight equal to 1/16 of a pound or approximately 28.35 grams.
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A rough measurement of size expressed as a power of 10. Two numbers differ by one order of magnitude if one is about 10 times larger than the other.
Ohm
The SI unit of electrical resistance. Named after Georg Ohm. Describes how much a material opposes the flow of electric current. Symbol: Ω.
P
Pound
An imperial unit of weight. One pound (lb) is approximately 0.4536 kilograms.
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A unit of volume equal to 2 cups or 16 fluid ounces (approximately 473 mL) in the US. The UK pint equals 20 imperial fluid ounces (~568 mL).
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Pounds per square inch. A unit of pressure commonly used in the US for tire pressure, hydraulics, and gas cylinders. 1 PSI ≈ 6,895 Pascals.
Pascal
The SI unit of pressure. Named after Blaise Pascal. 1 Pascal equals 1 Newton per square meter. Standard atmosphere = 101,325 Pa.
Pressure
Force applied per unit area. Calculated as force ÷ area. SI unit is the Pascal (Pa). Common in fluid mechanics, meteorology, and engineering.
Power
The rate at which energy is transferred or work is done over time. Power = Energy ÷ Time. SI unit is the watt (W).
Petabyte
A unit of digital data equal to 1,000 terabytes. Abbreviated PB. Used to describe large-scale data centers and internet traffic volumes.
Ping
A network utility that measures the round-trip time for data to travel from your device to a server and back. Low ping (e.g., <20 ms) is ideal for gaming and video calls.
Pip
The smallest price increment in currency trading. For most currency pairs, 1 pip = 0.0001 (e.g., EUR/USD moving from 1.0920 to 1.0921 is a 1-pip move).
Try the EUR to USD ConverterPurchasing Power Parity
An economic theory that adjusts exchange rates so that identical goods cost the same in different countries. Used to compare living standards internationally.
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How consistently a measurement can be repeated. Precise measurements are close to each other even if not accurate (close to the true value).
Prefix (Metric)
A word or symbol added before a unit to indicate a multiple or fraction. Examples: kilo- (×1,000), milli- (÷1,000), mega- (×1,000,000), micro- (÷1,000,000).
Pound-Force
A unit of force in the imperial system, abbreviated lbf. One pound-force equals about 4.448 newtons. It is the gravitational force on a one-pound mass at Earth's surface.
Pound-Foot
An imperial unit of torque, abbreviated lb-ft. One lb-ft equals about 1.356 newton-meters. Common in US automotive specifications.
Q
Quart
A unit of volume equal to 2 pints or 4 cups. One US quart equals approximately 0.946 liters. One UK quart equals approximately 1.136 liters.
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The second currency in a currency pair. In EUR/USD, the US dollar is the quote currency. If EUR/USD = 1.09, one euro buys 1.09 US dollars.
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Recipe Conversion
The process of scaling a recipe's ingredient quantities up or down. For example, doubling a recipe requires doubling all ingredients while keeping ratios consistent.
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A comparison of two quantities by division. For example, the ratio of miles to kilometers is approximately 1:1.609. Used in conversion factors and scaling.
Try the Miles to KM ConverterResistance
The opposition to the flow of electric current through a material. Measured in ohms (Ω). Higher resistance means less current flows for a given voltage (Ohm's Law: V = IR).
Rounding
Reducing the number of digits in a result while keeping its value close to the original. Important in conversions to avoid false precision in answers.
Radian
The SI unit of angle. A full circle is 2π (about 6.283) radians. One radian equals about 57.296°. Used in mathematics and physics because it simplifies formulas involving rotation.
S
SI Units
The International System of Units (Système International), the modern form of the metric system. It is the world's most widely used system of measurement.
Stone
A unit of weight used primarily in the UK and Ireland equal to 14 pounds or approximately 6.35 kilograms. Commonly used to express body weight.
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A unit of weight used in the United States equal to 2,000 pounds or approximately 907.2 kilograms. Different from the metric ton and the long ton.
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A unit of area equal to a square with sides one foot long. One square foot equals approximately 0.0929 square meters. Common in US real estate.
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The SI unit of area. One square meter equals 10.764 square feet. Commonly used worldwide for room sizes and property measurements.
Try the Square Meters to Square Feet ConverterSquare Kilometer
A metric unit of area equal to one million square meters or approximately 0.386 square miles. Used to measure cities, countries, and large land areas.
Try the Square Meters to Square Feet ConverterSquare Mile
An imperial unit of area equal to 640 acres or approximately 2.59 square kilometers. Used to measure large geographic areas in the US and UK.
Try the Acres to Square Feet ConverterSquare Yard
An imperial unit of area equal to 9 square feet or approximately 0.836 square meters. Used in flooring and fabric measurements.
Try the Square Feet to Square Meters ConverterSquare Inch
An imperial unit of area equal to a square with 1-inch sides. One square inch equals approximately 6.45 square centimeters.
Try the Square Feet to Square Meters ConverterSpeed of Light
The speed at which light travels in a vacuum: approximately 299,792,458 meters per second (about 186,282 miles per second). Denoted as c.
Speed
The rate at which an object covers distance over time. Measured as distance divided by time. Common units include mph, km/h, and m/s.
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The SI base unit of time. Defined as exactly 9,192,631,770 oscillations of a cesium-133 atom. There are 60 seconds in a minute.
Scientific Notation
A way of expressing very large or very small numbers using powers of 10. Example: 6,000,000 = 6 × 10⁶; 0.0000045 = 4.5 × 10⁻⁶.
Significant Figures
The meaningful digits in a measurement that carry information about its precision. Example: 3.14 has three significant figures; 0.00456 has three significant figures.
Spot Rate
The current exchange rate at which a currency can be immediately bought or sold. Also called the 'spot price.' Used for on-the-spot currency conversions.
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In measurement, a ratio representing the relationship between a measurement on a model or map and the actual measurement. Also refers to a device used to measure weight.
Try the Pounds to KG ConverterSpecific Gravity
The ratio of a substance's density to the density of water. Being a ratio, it has no units. A specific gravity of 2 means the substance is twice as dense as water.
T
Temperature
A measure of the warmth or coldness of an object or substance. Common scales include Celsius, Fahrenheit, and Kelvin.
Try the Fahrenheit to Celsius ConverterTroy Ounce
A unit of mass used for precious metals equal to approximately 31.1 grams — slightly heavier than a standard avoirdupois ounce (28.35 g).
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A unit of volume used in cooking equal to 3 teaspoons or approximately 14.79 milliliters. Abbreviated as tbsp.
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A unit of volume used in cooking equal to 1/3 of a tablespoon or approximately 4.93 milliliters. Abbreviated as tsp.
Try the Tablespoons to Cups ConverterTemperature Conversion
The process of expressing a temperature in a different scale. Common conversions: °F to °C: subtract 32 then multiply by 5/9. °C to K: add 273.15.
Try the Fahrenheit to Celsius ConverterTerabyte
A unit of digital data equal to 1,000 gigabytes (SI). Abbreviated TB. Hard drives and cloud storage are commonly measured in terabytes.
Tolerance
In engineering, the acceptable range of variation in a measurement. A tolerance of ±0.01 mm means the actual dimension can vary by up to 0.01 mm from the target.
Try the CM to Inches ConverterTorque
A measure of the turning force on an object, calculated as force times the distance from the pivot. Measured in newton-meters (Nm) or pound-feet (lb-ft). Engine output is often quoted in these units.
U
US Customary Units
A system of measurement used in the United States that largely derived from the British imperial system. Includes inches, feet, miles, pounds, and gallons.
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The process of expressing a measurement in a different unit while keeping the same value. For example, converting 5 km to 5,000 m or 3.107 miles.
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Volume
A measure of the amount of space a substance or object occupies. Common units include liters, gallons, and cubic meters.
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The SI unit of electrical potential (voltage). Named after Alessandro Volta. 1 volt = 1 joule per coulomb. Household electricity is typically 120V (US) or 230V (Europe).
Voltage
The electrical potential difference between two points in a circuit. Measured in volts (V). Sometimes called electromotive force (EMF). It 'pushes' current through a circuit.
W
Weight
A measure of how heavy an object is. Common units include pounds (imperial) and kilograms (metric).
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A unit of time equal to 7 days or 168 hours. Widely used in scheduling, calendars, and work cycles worldwide.
Watt
The SI unit of power equal to one joule per second. Named after James Watt. Used to measure the rate of energy transfer in electrical and mechanical systems.
Wattage
The amount of power consumed by an electrical device, measured in watts. Calculated as Voltage × Current (W = V × A). A 60W bulb uses 60 watts of power.
Y
Yard
An imperial unit of length equal to 3 feet or 36 inches (approximately 0.9144 meters). Used in US football field measurements.
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A unit of time equal to 365 days (366 in a leap year), approximately the time it takes Earth to orbit the Sun once.