Convert km to astronomical units
Kilometers to astronomical units. Enter a value to convert, or use the km to astronomical units chart further down the page.
1 kilometer equals 6.684587122e-9 astronomical units. Going the other way, 1 astronomical unit = 149,597,870.7 kilometers.
How to convert km to astronomical units
To convert kilometers to astronomical units, multiply the kilometer value by 6.684587122e-9. You can also divide by 149597870.7 to get the same answer.
au = km × 6.684587122e-9
Worked example
Convert 15 km to astronomical units:
15 km = 0.0000001002688068 au
km to astronomical units conversion chart
Use this km to astronomical units table for quick reference without typing anything.
| kilometers (km) | astronomical units (au) |
|---|---|
| 0.01 km | 6.684587122e-11 au |
| 0.1 km | 6.684587122e-10 au |
| 1 km | 6.684587122e-9 au |
| 2 km | 1.336917424e-8 au |
| 3 km | 2.005376137e-8 au |
| 5 km | 3.342293561e-8 au |
| 10 km | 6.684587122e-8 au |
| 20 km | 0.0000001336917424 au |
| 50 km | 0.0000003342293561 au |
| 100 km | 0.0000006684587122 au |
| 1,000 km | 0.000006684587122 au |
What is a kilometer?
The kilometer is one thousand meters and is the standard unit for road distances and long-range measurement almost everywhere outside the United States and the United Kingdom.
What is an astronomical unit?
The astronomical unit is defined as exactly 149,597,870,700 meters, close to the mean Earth–Sun distance.
Frequently asked questions
How many astronomical units are in a kilometer?
1 km equals 6.684587122e-9 astronomical units. Going the other way, 1 astronomical units is 149,597,870.7 km.
How do you convert km to astronomical units?
To convert kilometers to astronomical units, multiply the kilometer value by 6.684587122e-9. You can also divide by 149597870.7 to get the same answer.
What is 10 km in astronomical units?
10 km equals 6.684587122e-8 astronomical units. The conversion chart on this page lists the other values people look up most often.
Related length conversions
Convert km to other units
- astronomical units to km
- km to mm
- km to cm
- km to meters
- km to inches
- km to feet
- km to yards
- km to miles
- km to micrometers
- km to nanometers
Convert other units to astronomical units
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