Convert mg/g to g/kg or back with the same numeric mass fraction, plus percent, ppm, amount per 100 g, and solute mass for an optional sample.

Enter mg/g and read the same concentration in g/kg.

The denominator is total sample mass, including the solute. A mass fraction is limited to 0–1,000 mg/g (0–100%).

Sample mass (optional)

Leave blank to omit the sample amount.

mg/g to g/kg Formula

The following relationship is used to convert milligrams per gram (mg/g) to grams per kilogram (g/kg).

g / kg = mg / g

This can also be shown by converting the numerator and denominator at the same time:

g / kg = mg / g × (1 g) / (1000 mg) × (1000 g) / (1 kg) = mg / g

Variables:

  • mg/g is the concentration in milligrams per gram
  • g/kg is the concentration in grams per kilogram
  • The numerical value remains the same when converting from mg/g to g/kg

To convert mg/g to g/kg, keep the same number and change the units from mg/g to g/kg.

What is mg/g to g/kg Conversion?

mg/g to g/kg conversion expresses the same mass fraction using different units: milligrams of a component per gram of total sample, or grams per kilogram of total sample. The total includes the component itself, so this converter accepts 0–1,000 mg/g (equivalently 0–1,000 g/kg or 0–100%). Numerator and denominator scaling cancel, leaving the numeric value unchanged. A denominator such as solvent-only mass is a different basis. An optional nonnegative total sample mass adds the component amount; leaving it blank omits that calculation.

How to Convert mg/g to g/kg?

The following steps outline how to convert mg/g to g/kg.

  1. First, determine the concentration in milligrams per gram (mg/g).
  2. Next, recognize that mg/g and g/kg represent the same mass-per-mass ratio.
  3. Finally, write the same numerical value with units of g/kg.
  4. After inserting the value and calculating the result, check your answer with the calculator above.

Example Problem: 

Use the following variables as an example problem to test your knowledge.

Concentration = 5 mg/g

Converted Value = 5 g/kg

mg/g to g/kg Conversion Table

The table below lists several example values in mg/g and their equivalent values in g/kg.

Concentration mg/g g/kg
Very Low Level 0.5 0.5
Reference Value 1 1
Moderate Level 2 2
Higher Level 5 5
Concentrated Sample 10 10

Laboratories, technical reports, and product specifications may use either mg/g or g/kg depending on formatting preferences. Knowing that the numeric value stays the same makes it easy to compare results across documents.