Converting Mass to Volume
Converting milligrams (mg) to teaspoons (tsp) is not a straightforward metric conversion. This is because milligrams measure mass (weight), while teaspoons measure volume (space occupied).
The Importance of Density
To convert mg to tsp, you must know the density of the substance. For example, a teaspoon of lead would weigh significantly more than a teaspoon of feathers. In the kitchen or pharmacy, we use the specific gravity of the ingredient to determine how many milligrams fill a standard 5mL teaspoon.
- Water: 1 teaspoon is approximately 5,000 mg.
- Sugar: 1 teaspoon is approximately 4,200 mg.
- Salt: 1 teaspoon is approximately 5,900 mg.
Standard Teaspoon Sizes
This calculator uses the standard US teaspoon, which is defined as exactly 4.92892 milliliters. In many clinical and nutritional contexts, this is rounded to a 5mL 'metric' teaspoon for simplicity.
Formula:
Volume Calculation:
Teaspoons = (Mass in mg / 1000) / (Density in g/mL × 4.929)