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Astronomical unit (au)

The mean Earth–Sun distance, exactly 149,597,870,700 meters.

Result149,597,870,700,000

1 astronomical unit = 149,597,870,700,000 millimeters

Astronomical unit at a glance

Unit nameAstronomical unit (plural: astronomical units)
Symbolau
Quantity measuredLength
Measurement systemSI
Also known asau, ua
Definition exact?Yes — exact by definition

1 astronomical unit in other length units

Unit1 au equals
Nanometer1.49597871 × 10²⁰ nm
Micrometer1.49597871 × 10¹⁷ µm
Millimeter149,597,870,700,000 mm
Centimeter14,959,787,070,000 cm
Decimeter1,495,978,707,000 dm
Meter149,597,870,700 m
Kilometer149,597,871 km
Inch5,889,679,948,819 in
Foot490,806,662,402 ft
Yard163,602,220,801 yd
Mile92,955,807.3 mi
Nautical mile80,776,388.1 nmi
Angstrom1.49597871 × 10²¹ Å
Mil5.88967995 × 10¹⁵ mil
Fathom81,801,110,400 ftm
Rod29,745,858,327 rd
Chain7,436,464,582 ch
Furlong743,646,458 fur
League30,985,269.1 lea
Light-year0.000015813 ly
Parsec0.000004848 pc

Frequently asked questions

What is a astronomical unit?
The mean Earth–Sun distance, exactly 149,597,870,700 meters.
What is the symbol for the astronomical unit?
The symbol for the astronomical unit is au. It measures length.
How many millimeters are in a astronomical unit?
1 astronomical unit = 149,597,870,700,000 millimeters.
How many centimeters are in a astronomical unit?
1 astronomical unit = 14,959,787,070,000 centimeters.
How many meters are in a astronomical unit?
1 astronomical unit = 149,597,870,700 meters.