km to AU
92 unitsConvert Kilometer to Astronomical unit (km to AU)
1 kilometer = 6.684587e-9 astronomical units. Convert kilometers to astronomical units instantly, with the exact factor, the formula and a reference table of common values.
km to AU conversion table
| km | AU |
|---|---|
| 1 km | 6.684587e-9 AU |
| 2 km | 1.336917e-8 AU |
| 3 km | 2.005376e-8 AU |
| 5 km | 3.342294e-8 AU |
| 10 km | 6.684587e-8 AU |
| 20 km | 1.336917e-7 AU |
| 50 km | 3.342294e-7 AU |
| 100 km | 6.684587e-7 AU |
| 250 km | 0.000001671146781 AU |
| 500 km | 0.000003342293561 AU |
| 1000 km | 0.000006684587123 AU |
What is a kilometer?
A kilometer is 1,000 meters. The prefix "kilo" always means one thousand, so the math never changes. Most of the world measures road distances and running races in kilometers, which is why road signs outside the United States and the United Kingdom count down in km.
It takes an average walker about 12 minutes to cover a kilometer, and a car on an open highway crosses one in well under a minute. A 5K race is five kilometers, and a marathon is a little over 42 kilometers.
In writing, the kilometer is usually shortened to "km". One kilometer is 1000 meters, and that ratio is what every figure on this page is built from.