Light-years (ly) to Kilometers (km) Conversion
Light-years
The light-year is a unit of astronomical distance equal to the distance that light travels in a vacuum in one Julian year (365.25 days), approximately 9.461 × 10¹⁵ metres. Despite containing the word "year," it is strictly a unit of distance, not time. The nearest star system, Alpha Centauri, is approximately 4.37 light-years away, while the observable universe extends approximately 46 billion light-years in every direction.
Kilometers
The kilometre, equal to exactly 1,000 metres, is the standard unit for measuring distances at a geographic and infrastructural scale, including road distances, flight paths, and the dimensions of countries and continents. It is derived directly from the metre by applying the SI prefix kilo- (from Greek khilioi, meaning thousand) and is universally used in science, meteorology, and everyday life in all countries that have adopted the metric system. The Earth's circumference at the equator is approximately 40,075 km, a value historically used in the original derivation of the metre itself.
| Light-years (ly) | Kilometers (km) |
|---|---|
| 0.1 ly | 946,073,047,258.0801 km |
| 1 ly | 9,460,730,472,580.80 km |
| 2 ly | 18,921,460,945,161.60 km |
| 3 ly | 28,382,191,417,742.402 km |
| 5 ly | 47,303,652,362,904.00 km |
| 10 ly | 94,607,304,725,808.00 km |
| 20 ly | 189,214,609,451,616.00 km |
| 30 ly | 283,821,914,177,424.00 km |
| 50 ly | 473,036,523,629,040.06 km |
| 100 ly | 946,073,047,258,080.10 km |
| 1000 ly | 9,460,730,472,580,800.00 km |
Frequently Asked Questions (FAQ)
How many kilometers are in 1 light-years?
1 light-years (ly) is exactly 9,460,730,472,581 kilometers (km).
How do I convert light-years to kilometers?
Multiply the value in light-years by 9,460,730,472,581 to get the result in kilometers. Or use the converter above — type any number and see the result instantly.