Millimeters to Astronomical Units

Millimeter

A millimeter (mm) is a small metric unit of length equal to one-thousandth of a meter. It is ideal for precise measurements like product packaging, engineering drawings, and small household objects. Many rulers and calipers include millimeter markings to help measure with accuracy.

Since 10 millimeters = 1 centimeter, converting between nearby metric units is simple. When switching to imperial units—for example, 1 mm ≈ 0.03937 inches—a conversion tool offers quick and accurate results.

Astronomical Unit

An astronomical unit (AU) is a standard space measurement based on the distance from the Earth to the Sun—about 149.6 million kilometers or 93 million miles. It helps describe solar system distances in practical numbers rather than extremely large values.

Astronomers use AU values to measure orbits of planets, asteroids, and comets relative to Earth.