Conversion Glossary

Standard atmospheric pressure at sea level, defined as 101,325 Pa.

A pressure unit equal to 100,000 pascals, slightly less than one atmosphere.

Base-2 number system using only 0 and 1, the native language of digital electronics.

Body Mass Index — weight in kg divided by height in m². Used as a population-level weight screen.

British Thermal Unit — the energy to heat one pound of water by 1°F (≈ 1,055 J).

A unit of digital information equal to 8 bits — typically the size of one character.

The energy to heat 1 g of water by 1°C — 4.184 joules. The 'food Calorie' is 1,000 of these.

Metric temperature scale where water freezes at 0° and boils at 100° at standard pressure.

A cooking volume measure — US 236.6 ml, metric 250 ml, UK 284 ml.

US temperature scale where water freezes at 32° and boils at 212°.

An imperial unit of length equal to exactly 0.3048 meters.

1,073,741,824 bytes (2³⁰) — the binary equivalent of a gigabyte, used by most operating systems.

Base-16 number system using 0–9 and A–F — compact representation of binary data.

A family of British-origin units (foot, pound, gallon, Fahrenheit) still used officially in the United States.

An imperial unit equal to 25.4 millimeters; 12 inches make one foot.

The SI unit of energy — the work done by one newton acting over one meter.

The SI temperature unit, measured from absolute zero. K = °C + 273.15.

The SI base unit of mass, defined since 2019 by the Planck constant.

A metric unit of distance equal to 1,000 meters.

The energy delivered by one kilowatt of power over one hour (3.6 MJ).

A metric unit of volume equal to one cubic decimeter (1,000 cm³).

1,000,000 bytes in SI decimal usage. Not to be confused with the binary mebibyte (MiB).

The SI base unit of length, defined as the distance light travels in 1/299,792,458 of a second.

An imperial unit of distance equal to 1,609.344 meters.

A loan secured by real estate, typically repaid over 15–30 years with equal monthly payments.

1,852 meters — the standard unit of distance at sea and in aviation.

An imperial unit of mass equal to 1/16 of a pound, or 28.3495 grams.

The SI unit of pressure equal to one newton per square meter.

An imperial unit of mass equal to exactly 0.45359237 kilograms.

Pounds per square inch — imperial pressure unit equal to 6,894.76 Pa.

A way of writing numbers as a coefficient between 1 and 10 multiplied by a power of ten.

The International System of Units — the modern metric system used worldwide for science and trade.

A British unit of mass equal to 14 pounds (6.35 kg), used for body weight.

An imperial volume equal to 3.78541 liters. The UK gallon is larger (4.546 L).