Light-year to Kilometer
Convert Light-year to Kilometer instantly. Free online astronomy unit converter with exact formula, conversion table and FAQ.
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Formula
kilometer = light-year × 9.46073047e+12
light-year = kilometer × 1.05700083e-13
Conversion table
| 1 ly | 9.46073047e+12 km |
| 5 ly | 4.73036524e+13 km |
| 10 ly | 9.46073047e+13 km |
| 20 ly | 1.89214609e+14 km |
| 50 ly | 4.73036524e+14 km |
| 100 ly | 9.46073047e+14 km |
| 500 ly | 4.73036524e+15 km |
| 1,000 ly | 9.46073047e+15 km |
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Frequently asked questions
What is the source unit in this conversion?
The source unit is the light-year (ly). A light-year is the distance light travels in one Julian year through a vacuum.
What is the destination unit in this conversion?
The destination unit is the kilometer (km). A kilometer is a metric unit of length equal to 1,000 meters.
How do I convert light-year to kilometer?
Multiply the light-year value by 9.46073047e+12. For example, 10 ly × 9.46073047e+12 = 9.46073047e+13 km.
Is the light-year to kilometer conversion exact?
Yes. Both units have a fixed, defined relationship to the astronomy converter's distance base unit, so the conversion factor is exact rather than a measured approximation.
Where is this conversion commonly used?
It's used in astronomy, physics, and space science whenever a distance value expressed in light-year needs to be compared with, or reported in, kilometer.
Can I convert kilometer back to light-year?
Yes. Multiply the kilometer value by 1.05700083e-13 to get light-year.
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About this conversion
This page converts light-year (ly) to kilometer (km) within the astronomy converter.
A light-year is the distance light travels in one Julian year through a vacuum.
A kilometer is a metric unit of length equal to 1,000 meters.
The formula is kilometer = light-year × 9.46073047e+12, based on each unit's fixed relationship to the astronomy converter's distance base unit.
The conversion is exact, since it relies on a fixed numerical ratio between the two units rather than a measured or approximate value.
Use the calculator above for instant results, or the table below for common light-year values already converted to kilometer.