# Parsecs to Light years Converter

Use this converter to easily convert between Parsecs and Light years (pc to ly).

pc
ly
Share converter:

Embed this tool:
get code

## How many Light years equal one Parsec?

Approximately 3.26 light years equal one parsec. With accuracy to six decimal places, one parsec is equal to 3.261563 light years. The international symbol for light years is "ly" whereas for parsec it is "pc" so using this notation 1pc = 3.26ly.

## Difference between Parsecs and Light years

Parsecs were historically used because distances between astronomical bodies were measured using the trigonometric parallax method. The parsec is defined as the distance at which a star will show an annual parallax of one arcsecond, meaning it is based on two arbitrary quantities, characteristic of an Earth-based observer. One is the radius of our planet's orbit and the other is the choice to divide a circle in 360 degrees. This makes it ill-suited as a universally applicable unit.

On the other hand, light years express the distance covered by light in one year's time and while a year is an Earth-based time slice, it does not depend on other quantities except for the speed of light which is a universal constant. It can be argued that the light year is therefore a more suitable unit for distances on the astronomical scale.

## How to convert Parsecs to Light years?

Knowing that 1 parsec equals 3.26 light-years, to convert from pc to ly one needs to divide the measurement in parsecs by 3.26 in order to get the light-years equivalent. See the example below for a detailed calculation. Of course, using our pc to ly converter above is much easier.

#### Light years to parsecs conversion example

Sample task: convert 2 parsecs to light years. Solution:

Formula:
pc * 3.261563 = ly
Calculation:
2 pc * 3.2616 = 6.523126 ly
End result:
2 pc is equal to 6.523126 ly

## pc to ly conversion table

pc to ly conversion table
pc ly
1 pc 3.261563 ly
2 pc 6.523126 ly
3 pc 9.784689 ly
4 pc 13.046252 ly
5 pc 16.307815 ly
6 pc 19.569378 ly
7 pc 22.830941 ly
8 pc 26.092504 ly
9 pc 29.354067 ly
10 pc 32.615630 ly
20 pc 65.231260 ly
30 pc 97.846890 ly
40 pc 130.462520 ly
50 pc 163.078150 ly
60 pc 195.693780 ly
70 pc 228.309410 ly
80 pc 260.925040 ly
90 pc 293.540670 ly
100 pc 326.156300 ly
200 pc 652.312600 ly
300 pc 978.468900 ly
400 pc 1,304.625200 ly
500 pc 1,630.781500 ly
600 pc 1,956.937800 ly
700 pc 2,283.094100 ly
800 pc 2,609.250400 ly
900 pc 2,935.406700 ly
1,000 pc 3,261.563000 ly

#### References

1 NIST Special Publication 330 (2008) - "The International System of Units (SI)", edited by Barry N.Taylor and Ambler Thompson

2 International Organization for Standardization (1993). ISO Standards Handbook: Quantities and units (3rd edition). Geneva: ISO. ISBN 92-67-10185-4.

#### Cite this converter & page

If you'd like to cite this online converter resource and information as provided on the page, you can use the following citation:
Georgiev G.Z., "Parsec to Light Years Converter", [online] Available at: https://www.gigacalculator.com/converters/convert-parsec-to-light-year.php URL [Accessed Date: 06 Jun, 2023].