---
title: "Kilometers to Light-years — km to ly converter"
description: "1 kilometer = 1.057 × 10^-13 light-years. Convert kilometers to light-years with a full conversion table, the exact formula, and a calculator for any value."
url: https://atoneplace.net/convert/km-to-light-years/
site: "At One Place"
---

# Kilometers to light-years

**1 kilometer in light-years: 1 km = 1.057 × 10^-13 ly**

ly = km × 1.057000834 × 10^-13

To convert kilometers to light-years, multiply by 1.057000834 × 10^-13. The table below gives the values people look up most often, and the converter works for any number.

## Kilometers to light-years table

*Common kilometer values converted to light-years.*

| Kilometers | Light-years |
| --- | --- |
| 1 km | 1.057 × 10^-13 |
| 2 km | 2.114 × 10^-13 |
| 3 km | 3.171 × 10^-13 |
| 4 km | 4.228 × 10^-13 |
| 5 km | 5.285 × 10^-13 |
| 10 km | 1.057 × 10^-12 |
| 15 km | 1.586 × 10^-12 |
| 20 km | 2.114 × 10^-12 |
| 25 km | 2.643 × 10^-12 |
| 30 km | 3.171 × 10^-12 |
| 40 km | 4.228 × 10^-12 |
| 50 km | 5.285 × 10^-12 |
| 75 km | 7.928 × 10^-12 |
| 100 km | 1.057 × 10^-11 |
| 250 km | 2.643 × 10^-11 |
| 500 km | 5.285 × 10^-11 |
| 1,000 km | 1.057 × 10^-10 |

## How the conversion works

The relationship is ly = km × 1.057000834 × 10^-13. Both units measure length, so the conversion is a fixed factor that never changes.

## Common questions

### How many light-years are in one kilometer?

One kilometer equals 1.057 × 10^-13 light-years. ly = km × 1.057000834 × 10^-13.

### How do you convert kilometers to light-years?

Use ly = km × 1.057000834 × 10^-13. So 10 km is 1.057 × 10^-12 ly.

### How many kilometers are in one light-year?

One light-year equals 9,460,730,500,000 kilometers, which is the reverse of the conversion above.

## Related pages

- [Light-years to Kilometers](https://atoneplace.net/convert/light-years-to-km/)
- [Kilometers to Meters](https://atoneplace.net/convert/km-to-meters/)
- [Kilometers to Centimeters](https://atoneplace.net/convert/km-to-cm/)
- [Kilometers to Millimeters](https://atoneplace.net/convert/km-to-mm/)
- [Kilometers to Miles](https://atoneplace.net/convert/km-to-miles/)
- [Kilometers to Yards](https://atoneplace.net/convert/km-to-yards/)
- [Kilometers to Feet](https://atoneplace.net/convert/km-to-feet/)
- [Kilometers to Inches](https://atoneplace.net/convert/km-to-inches/)

## Sources

- Guide for the Use of the International System of Units (SP 811) — NIST (https://www.nist.gov/pml/special-publication-811) [Public domain (US Government)]
- The International System of Units (SI Brochure) — Bureau International des Poids et Mesures (https://www.bipm.org/en/publications/si-brochure)
- Calculated on this page — At One Place (/about/)