Light Years Converter
Convert between light-years and kilometres or miles.
Quick answer: enter your details below and click Convert Distance — your result appears instantly, right here in your browser. Nothing you enter is uploaded or stored.
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How to use
- Enter a distance.
- Pick the conversion direction.
- Click Convert Distance.
About this tool
Enter a distance and pick a direction. One light-year is about 9.461 trillion kilometres, and the tool multiplies or divides by that figure. It is an astronomy unit conversion, not a travel-time estimate.
Frequently asked questions
Is a light-year a unit of time?
No. It is the distance light travels in one year in a vacuum.
Why are the numbers so large?
Light moves at about 300,000 km per second, so a year of travel covers trillions of kilometres.