Convert light-years to millimeters
1 ly = 9460730472580000000 mm — exactly. Both units are defined against the SI, so this factor is a fraction, not an approximation.
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Show this value in all 50 length units
- Gigameters Gm 9 460 730.472 58
- Megameters Mm 9 460 730 472.58
- Kilometers km 9 460 730 472 580
- Hectometers hm 94 607 304 725 800
- Decameters dam 946 073 047 258 000
- Meters m 9 460 730 472 580 000
- Decimeters dm 9.46073047258e+16
- Centimeters cm 9.46073047258e+17
- Millimeters mm 9.46073047258e+18
- Micrometers µm 9.46073047258e+21
- Nanometers nm 9.46073047258e+24
- Picometers pm 9.46073047258e+27
- Femtometers fm 9.46073047258e+30
- Inches in 3.72469703645e+17
- Feet ft 3.10391419704e+16
- Yards yd 1.03463806568e+16
- Miles mi 5 878 625 373 180
- Nautical miles nmi 5 108 385 784 330
- Thous thou 3.72469703645e+20
- Hands hh 9.31174259112e+16
- Links li 4.70290029855e+16
- Spans span 4.13855226272e+16
- Cubits cubit 2.06927613136e+16
- Ells ell 8 277 104 525 440 000
- Fathoms ftm 5 173 190 328 400 000
- Rods rd 1 881 160 119 420 000
- Chains ch 470 290 029 855 000
- Furlongs fur 47 029 002 985 500
- Leagues lea 1 959 541 791 060
- Barleycorns barleycorn 1.11740911093e+18
- US survey feet ft (US) 3.10390798921e+16
- US survey miles mi (US) 5 878 613 615 930
- Ångströms Å 9.46073047258e+25
- Microns µ 9.46073047258e+21
- Bohr radiuss a₀ 1.78781895442e+26
- Planck lengths ℓₚ 5.85348875801e+50
- Astronomical units au 63 241.077 084 3
- Light-years ly 1
- Light-seconds ls 31 557 600
- Light-minutes lmin 525 960
- Parsecs pc 0.306 601 393 786
- Kiloparsecs kpc 0.000 306 601 393 786
- Megaparsecs Mpc 0.000 000 306 601 393 786
- Solar radiuss R☉ 13 598 865.1324
- Earth radiuss R🜨 1 484 967 897.12
- Point (DTP)s pt 2.68178186624e+19
- Picas pc 2.23481822187e+18
- Scandinavian miles mil 946 073 047 258
- Versts вер 8 868 326 277 260
- Lis 里 18 921 460 945 200
Every row is Light-year (ly) converted through the meter, in exact rational arithmetic.
How to convert light-years to millimeters
Multiply the number of light-years by 9460730472580000000 to get millimeters.
The exact factor is 9460730472580800000 .
Light-year: Light travelling for one Julian year (365.25 days) in vacuum — exact, since both inputs are defined values.
Light-year to Millimeter conversion table
| Light-years (ly) | Millimeters (mm) |
|---|---|
| 1 ly | 9.4607305e+18 |
| 2 ly | 1.8921461e+19 |
| 3 ly | 2.8382191e+19 |
| 5 ly | 4.7303652e+19 |
| 10 ly | 9.4607305e+19 |
| 20 ly | 1.8921461e+20 |
| 25 ly | 2.3651826e+20 |
| 50 ly | 4.7303652e+20 |
| 100 ly | 9.4607305e+20 |
| 250 ly | 2.3651826e+21 |
| 500 ly | 4.7303652e+21 |
| 1000 ly | 9.4607305e+21 |
Millimeter to Light-year conversion table
| Millimeters (mm) | Light-years (ly) |
|---|---|
| 1 mm | 1.0570008e-19 |
| 2 mm | 2.1140017e-19 |
| 3 mm | 3.1710025e-19 |
| 5 mm | 5.2850042e-19 |
| 10 mm | 1.0570008e-18 |
| 20 mm | 2.1140017e-18 |
| 25 mm | 2.6425021e-18 |
| 50 mm | 5.2850042e-18 |
| 100 mm | 1.0570008e-17 |
| 250 mm | 2.6425021e-17 |
| 500 mm | 5.2850042e-17 |
| 1000 mm | 1.0570008e-16 |
Frequently asked
How many millimeters are in a light-year?
One light-year equals 9.460730473e+18 millimeters (ly → mm). That figure is exact, not rounded.
How do you convert light-years to millimeters?
Multiply the number of light-years by 9460730472580000000 to get millimeters.
What is 1 mm in light-years?
One millimeter is 1.057000834e-19 light-years.
What is 10 ly in mm?
10 ly = 9.4607305e+19 mm.
What exactly is a light-year?
Light travelling for one Julian year (365.25 days) in vacuum — exact, since both inputs are defined values.