acalculator

How do I convert mg to kg?

Type a value in either box, and the answer shows it in the other unit as you type.

Your numbers

Kilograms (kg)
0.000001

1 mg = 0.000001 kg.

Kilograms (kg): 0.000001. 1 mg = 0.000001 kg.

Kilograms (kg) by milligrams (mg)

How to calculate

Converts milligrams (mg) to kilograms (kg) and back, with the exact unit definitions.

Example with the default inputs (Milligrams (mg) 1): 1 mg = 0.000001 kg.

Formula: kg = mg × 0.000001

  • 1 milligram = 0.000001 kilograms, from the exact definitions in NIST SP 811.
  • The answer shows at most 6 decimal places; the calculation keeps full precision.

Machine-readable copies: Markdown, JSON.

Worked examples

Each example is checked against the calculator on every build.

  1. Milligrams (mg) 1 gives Kilograms (kg) 0.000001.Source: Exact unit definitions in NIST SP 811 (2008), Appendix B.8
  2. Milligrams (mg) 500 gives Kilograms (kg) 0.0005.Source: Exact unit definitions in NIST SP 811 (2008), Appendix B.8
  3. Kilograms (kg) 0.0005 gives Milligrams (mg) 500.Source: Exact unit definitions in NIST SP 811 (2008), Appendix B.8

Other questions people ask

How many kilograms are in a milligram?

1 milligram is 0.000001 kilograms, from the exact unit definitions (NIST SP 811).

How do I convert mg to kg?

Multiply by 0.000001: kg = mg × 0.000001. For example, 1 mg × 0.000001 = 0.000001 kg.

How do I convert kg back to mg?

Multiply by 1,000,000, or type the kilograms into the second box and the converter works it out. 1 kilogram is 1,000,000 milligrams.