Authoritative definitions of the International System of Units and SI prefixes.
Unit conversion
Milligrams to Grams Converter
1 mg = 0.001 g. Enter a value to convert mg to g, then use the formula and table below. Displayed digits may be rounded.
Weight & massInstant result
Decimals
Formula result = input × 0.000001 ÷ 0.001. 1 mg = 0.001 g
Nonzero results too small for the selected decimal places use scientific notation.
Nonzero results too small for the selected decimal places use scientific notation.
Common examples
One value, several units
Kilograms1.00000e-6 kg
Grams0.001 g
Metric tonnes1.00000e-9 t
Pounds2.20462e-6 lb
Ounces3.52740e-5 oz
Stone1.57473e-7 st
Conversion table
| mg | g |
|---|---|
| 1 mg | 0.001 g |
| 2 mg | 0.002 g |
| 5 mg | 0.005 g |
| 10 mg | 0.01 g |
| 25 mg | 0.025 g |
| 50 mg | 0.05 g |
| 100 mg | 0.1 g |
Conversion chart
1 mg0.001 g
5 mg0.005 g
10 mg0.01 g
25 mg0.025 g
50 mg0.05 g
Worked example
1 mg = 0.001 g. Apply the selected conversion formula to other input values.
Unit definition
Milligrams (mg) One milligrams equals 0.000001 kilogram.
Unit history
Milligrams is represented here using its modern SI definition or an internationally accepted relationship to an SI base unit.
Step by step
1. Parse the value, including fractions.
2. Convert mg to kilogram.
3. Convert the base value to g and apply your display precision.
Understand the result before using it
Milligrams to Grams converts a value measured in Milligrams (mg) into the equivalent value in Grams (g). The numerical value changes because the size and definition of the selected unit changes; the underlying quantity does not.
Calculated result
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.
Formula, assumptions, and example
Formula
result = input × 0.000001 ÷ 0.001
Assumptions
- Milligrams and Grams represent the same weight & mass quantity.
- The input is expressed in mg; the output is expressed in g.
- The unit definitions and conventional relationship shown on this page apply.
Worked example
1 mg = 0.001 g. For another value, apply the same relationship and round only to the precision your source measurement supports.
When to use it
Good uses
- Read a mg measurement in a document that expects g.
- Compare a milligrams value with a value reported in grams.
- Check the mg to g arithmetic before copying the result into another calculation.
Limitations
Common mistakes to avoid
- Everyday language often says weight, but these units represent mass. Force requires a local gravitational acceleration.
- Round the output to a precision justified by the original measurement.
- Verify safety-critical, regulated, laboratory, and contractual conversions against the controlling standard.
Sources and further reading
These references explain the underlying standards or provide authoritative context. Your own contract, institution, clinician, product documentation, local code, or governing standard may be the controlling source.
Guidance on unit names, symbols, conversions, and numerical presentation.
Questions about this calculation
How do I convert Milligrams to Grams?
result = input × 0.000001 ÷ 0.001. Input is in mg; result is in g. 1 mg = 0.001 g. The displayed digits may be rounded.
What is 1 mg in g?
1 mg = 0.001 g. The displayed digits may be rounded.
Can I reverse the mg to g conversion?
Yes. Swap the source and target units in the converter. The reverse relationship converts g back to mg.
Is the Milligrams to Grams result exact?
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.