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.
9.46073047258e+18mm
Exact decimal: 9460730472580800000
1 ly = 9460730472580000000 mm
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.