📏 m to au — Meter to Astronomical Unit Converter

Convert length and distance units — meters, feet, inches, kilometers, miles, light years and more.

1 unit =
From
To
Formula 1 m = 6.6845e-12 au
UnitNameValue
0.001 m6.684e-15 au
0.01 m6.684e-14 au
0.1 m6.684e-13 au
1 m6.684e-12 au
5 m3.342e-11 au
10 m6.684e-11 au
50 m3.342e-10 au
100 m6.684e-10 au
1000 m6.68449e-09 au

How to convert Meter to Astronomical Unit

Multiply the number of Meters by 6.6845×10-12 to get Astronomical Units. Formula: au = m × 6.6845×10-12. Example: 10 m × 6.6845×10-12 = 6.6845×10-11 au. To reverse, divide Astronomical Units by 6.6845×10-12 to get Meters.

Worked examples

Example 1
1 m × 6.6845×10-12 = 6.6845×10-12 au
1 Meter equals 6.6845×10-12 Astronomical Unit.
Example 2
5 m × 6.6845×10-12 = 3.3422×10-11 au
5 Meter equals 3.3422×10-11 Astronomical Unit.
Example 3
10 m × 6.6845×10-12 = 6.6845×10-11 au
10 Meter equals 6.6845×10-11 Astronomical Unit.
Example 4 — reverse
1 au = 149600000000 m
To convert back from Astronomical Unit to Meter, divide by 6.6845×10-12 or use the swap button above.

Meter to Astronomical Unit — reference table

Meter (m)Astronomical Unit (au)
0.001 m6.6845×10-15 au
0.01 m6.6845×10-14 au
0.1 m6.6845×10-13 au
0.5 m3.3422×10-12 au
1 m6.6845×10-12 au
2 m1.3369×10-11 au
5 m3.3422×10-11 au
10 m6.6845×10-11 au
20 m1.3369×10-10 au
50 m3.3422×10-10 au
100 m6.6845×10-10 au
250 m1.6711×10-9 au
500 m3.3422×10-9 au
1000 m6.6845×10-9 au
10000 m6.6845×10-8 au

Quick conversion tips

1
Multiply by 6.6845×10-12

To convert Meter to Astronomical Unit, multiply by 6.6845×10-12. Example: 10 m = 6.6845×10-11 au

2
Reverse: divide by 6.6845×10-12

To convert Astronomical Unit back to Meter, divide by 6.6845×10-12 (multiply by 149600000000). Use the swap button above.

3
Round number check

Start with 100 Meters = 6.6845×10-10 au as your reference point. Scale up or down from there.

Where meter to astronomical unit conversion is used

Orbital mechanics

The AU is defined as exactly 149,597,870,700 metres. This exact SI definition means m-to-AU conversion is a fixed ratio embedded in every orbital mechanics calculation that converts between SI equations and astronomical distance notation.

Radar astronomy

Radar range measurements to planets and asteroids return distances in metres from signal travel time. These are converted to AU for astronomical reporting and back to metres for detailed orbital fitting calculations.

Solar system simulation

N-body simulation codes integrate orbits in SI units (metres, seconds) but display and compare results in AU for astronomical context — m-to-AU conversion is embedded in every solar system simulation output routine.

Spacecraft navigation

Deep-space navigation uses metres for precise position calculations while mission reports and trajectory summaries use AU — flight controllers convert between the two in every navigation update and trajectory correction manoeuvre.

Standards and metrology

The 2012 IAU definition of the AU as exactly 149,597,870,700 m makes m-to-AU conversion a cornerstone of international astronomical measurement standards and geodetic reference frame definitions.

Astronomy education

Teaching the scale of the solar system starts with the AU-to-metre definition: "1 AU = 149.6 billion metres." Students use this conversion to build intuition for planetary distances in both SI and astronomical units.

Frequently asked questions

1 Meter equals 6.6845×10-12 Astronomical Units. Multiply any Meter value by 6.6845×10-12 to get Astronomical Units.
10 Meters equals 6.6845×10-11 Astronomical Units. (10 × 6.6845×10-12 = 6.6845×10-11)
100 Meters equals 6.6845×10-10 Astronomical Units. (100 × 6.6845×10-12 = 6.6845×10-10)
Divide Astronomical Unit by 6.6845×10-12 to get Meters. Or multiply by 149600000000. Use the swap button on the converter above for instant reverse conversion.
Formula: au = m × 6.6845×10-12. Example: 5 m × 6.6845×10-12 = 3.3422×10-11 au.
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About Meter and Astronomical Unit

Meter (m)

The Meter is a unit of Length measurement (symbol: m). 1 m = 6.6845×10-12 au. Used in scientific and practical Length measurement applications.

Astronomical Unit (au)

The Astronomical Unit is a unit of Length measurement (symbol: au). It is part of an internationally recognised measurement system used alongside the Meter.

History & origin

The metre was born from the French Revolution's desire to replace the chaotic patchwork of pre-metric measurement with a rational, universal standard. In 1791 the French Academy of Sciences defined it as one ten-millionth of the distance from the equator to the North Pole along the Paris meridian — a unit based on Earth itself rather than any king's anatomy. Early platinum and platinum-iridium prototype bars were made in 1799 and 1889. In 1983, the metre was redefined permanently using the speed of light — exactly the distance light travels in 1/299,792,458 of a second. Today it is the world's most widely used unit of length.

The astronomical unit has ancient roots — Aristarchus of Samos attempted to measure the Earth-Sun distance around 270 BC. For centuries the AU was estimated using Venus transit observations. Edmond Halley organised the first coordinated international transit-of-Venus expedition in 1716. The modern value was determined by radar ranging to Venus in 1961. The IAU formally defined the AU as exactly 149,597,870,700 metres in 2012 — a fixed constant of physics, not a measured quantity.

Common use: Meter to Astronomical Unit conversion is needed when working with international standards, scientific publications, or reference materials that use different unit systems for Length measurement.