Light year to Astronomical unit Converter (and vice versa)

Created by: tinycalcs.com/en
Number of supported units: 2
Last update: 2026

This converter allows you to convert light years [ly] to astronomical units [au] or astronomical units [au] to light years [ly]. Calculations are performed in both directions. The calculation result and the entered value are displayed with up to 20 decimal places for maximum accuracy.

1 light year [ly] ≈ 63,241.0771 astronomical units [au]1 astronomical unit [au] ≈ 1.581 * 10-5 light years [ly]

Convert light years to astronomical units

There are two simple ways to convert light years [ly] to astronomical units [au]. In the first calculation method, the value in light years [ly] is divided by the rounded conversion factor of 1.581 * 10-5. The second method multiplies the value in light years [ly] by the rounded conversion factor of 63,241.0771.

  • Astronomical units [au] ≈ light years [ly] ÷ (1.581 * 10-5)
  • Astronomical units [au] ≈ light years [ly] * 63,241.0771

However, rounded conversion values are only suitable for rough conversions, as rounding errors can occur in the calculation result. The most accurate conversion of light years [ly] to astronomical units [au] can be achieved using the following calculation method.

  • Astronomical units [au] = light years [ly] * 3,981,712 * 23,760,459 ÷ 23,367 ÷ 64,021

Convert astronomical units to light years

Converting astronomical units [au] to light years [ly] is easy and can be done in two ways. The first method involves multiplication, in which the value in astronomical units [au] is multiplied by the rounded conversion factor of 1.581 * 10-5. The second variant is a division. Here, the value in astronomical units [au] is divided by the rounded conversion factor of 63,241.0771.

  • Light years [ly] ≈ astronomical units [au] * 1.581 * 10-5
  • Light years [ly] ≈ astronomical units [au] ÷ 63,241.0771

However, rounded conversion values do not allow for exact calculations because rounding errors can occur in the calculation result. The most accurate conversion of astronomical units [au] to light years [ly] can be achieved using the following calculation method.

  • Light years [ly] = astronomical units [au] ÷ 3,981,712 ÷ 23,760,459 * 23,367 * 64,021

Converter

Decimal places

How it's calculated

Factor: 
≈ 63,241.077
Astronomical units = Light years * 3,981,712 * 23,760,459 ÷ 23,367 ÷ 64,021
Light years = Astronomical units ÷ 3,981,712 ÷ 23,760,459 * 23,367 * 64,021

To all available units

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