parsec to light-year Converter
Convert pc to ly and back with a live reference table.
1 pc = 3.26156 ly\n5 pc = 16.3078 ly\n10 pc = 32.6156 ly\n25 pc = 81.5391 ly\n50 pc = 163.078 ly\n100 pc = 326.156 ly
Why this conversion matters
Parsecs are native to parallax astronomy, while light-years are often easier for public-facing distance explanations. The widget keeps the direction explicit so you can enter either side of the pair without doing the reciprocal by hand. It is built for quick checks where a calculator, specification sheet, recipe, map, or lab note uses the other unit.
For the default example, 5 pc converts to 16.3078 ly. Switching the direction shows the inverse relationship, so 16.3078 ly converts back to 5 pc with the same factor.
Formula and privacy note
The calculation uses 1 pc = 3.26156 ly. Forward conversion multiplies by that factor, and reverse conversion divides by it. Results are rounded to six significant figures for readable estimates, so very small scientific units and large planning units stay scannable. Check the unit labels before copying a result, especially when similar abbreviations appear in the same project. The reference table is generated from the same constant, and everything runs locally in your browser.
Frequently Asked Questions
What factor does this converter use?
It uses the standard factor 1 pc = 3.26156 ly, then applies the reciprocal for the reverse direction.
Why are results rounded?
The main result is rounded to six significant figures so very large and very small values stay readable while preserving the useful precision for quick checks.
Can I convert both directions?
Yes. Choose pc to ly or ly to pc from the direction menu and the output updates immediately.
Is this converter private?
Yes. The conversion runs entirely in your browser, and the value you enter is not uploaded or stored.
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