Select a category
Conversion Formula:
Convert Meter to Light Year (m to ly) instantly with accurate, readable results.
Use our Length Unit Converter to quickly convert between meters, kilometers, feet, inches, miles, and more. This powerful unit conversion tool supports both metric and imperial systems, making it ideal for travel, engineering, education, and everyday use. Whether you're calculating distances or comparing measurements, our length unit conversion calculator ensures fast and accurate results every time.
Meter (m) — the SI base unit of length
It is defined by fixing the speed of light in vacuum at exactly 299,792,458 m/s; a meter is the distance light travels in 1/299,792,458 of a second. Used worldwide for measuring distance and size in science, engineering, construction, and everyday life.
- Symbol: m
- System: SI base unit for length
- Exact relations: 1 m = 100 cm = 1000 mm
- Imperial equivalents (derived from 1 in = 0.0254 m exactly): 1 m = 39.37007874 in ≈ 3.28084 ft ≈ 1.09361 yd
- Typical examples: a doorway ~2 m tall; a city block ~100 m; a 400 m running track lap.
Light-year (ly) - astronomical distance
Light-year is an astronomical distance equal to the distance light travels in vacuum in one Julian year. Used for interstellar and intergalactic scales; based on c = 299,792,458 m/s and a Julian year of 365.25 days (31,557,600 s)
- Symbol: ly
- System: Astronomical (non-SI, accepted for use with SI)
- Defined relation: 1 ly = c × 31,557,600 s = 9.4607304725808×10^15 m ≈ 9.4607×10^12 km
- Other relations: 1 ly ≈ 63,241.077 AU; 1 ly ≈ 0.306601 pc; 1 pc ≈ 3.26156 ly
- Typical examples: Proxima Centauri ~4.2465 ly; Milky Way diameter ~1.0×10^5 ly; Andromeda Galaxy ~2.5×10^6 ly