Astronomical Unit Converter
Choose two distance units and enter a value. The conversion runs locally and uses fixed unit definitions; it does not fetch live astronomy data.
A QUICK WALKTHROUGH
How to use this tool
- Enter a finite distance and choose its source unit.
- Choose the destination unit and select Convert.
- Review the result and use Swap to reverse the units.
Fixed distance definitions
The converter uses exact SI definitions for the astronomical unit, metre, kilometre, and mile, plus fixed Julian, Gregorian, traditional, and tropical light-year factors. Parsecs are derived from the exact astronomical unit and the conventional 648000/π definition of a parsec.
Local and bounded
All arithmetic happens in this browser. No location, date, observatory, ephemeris, star catalogue, or live service is used. Inputs and converted results must be finite JavaScript Numbers; no physical distance cap is imposed.
GOOD TO KNOW
Common questions
Does this look up planets or stars?
No. It converts distances only and uses no live or large astronomy dataset.
Which light-year is used?
You can select Julian, Gregorian, traditional, or tropical/solar factors explicitly.
Are my inputs uploaded?
No. The calculation is performed locally in your browser.