Convert teaspoons to milligrams using substance density. Choose US or metric teaspoons, enter custom density when needed, or reverse the calculation from milligrams to teaspoons.
Water uses an approximate density of 1.000 g/mL.
Teaspoons measure volume while milligrams measure mass.
US and metric teaspoons have slightly different volumes.
Enter a verified substance density when water is not appropriate.
Calculate tsp to mg and mg to tsp as inputs change.
Keep the volume at one US teaspoon and move the density slider. Equal volumes can have different masses.
Enter teaspoons or milligrams.
Choose a US or metric teaspoon.
Select water or enter custom density.
Read the converted result.
Use Swap to reverse the same density-aware equation.
mg = tsp × 4.92892159375 × density(g/mL) × 1000mg = tsp × 5 × density(g/mL) × 1000tsp = mg ÷ (4.92892159375 × density × 1000)tsp = mg ÷ (5 × density × 1000)For 1 US teaspoon of water at approximately 1.000 g/mL:
1 x 4.92892159375 x 1 x 1000 = 4,928.92 mg≈ 4,928.92 mgGenerated with a water density of 1.000 g/mL. These values do not apply universally to other substances.
| Teaspoons | Milliliters | Milligrams |
|---|---|---|
| 0.25 tsp | 1.2322 mL | 1,232.23 mg |
| 0.5 tsp | 2.4645 mL | 2,464.46 mg |
| 0.75 tsp | 3.6967 mL | 3,696.69 mg |
| 1 tsp | 4.9289 mL | 4,928.92 mg |
| 1.5 tsp | 7.3934 mL | 7,393.38 mg |
| 2 tsp | 9.8578 mL | 9,857.84 mg |
| 2.5 tsp | 12.3223 mL | 12,322.3 mg |
| 3 tsp | 14.7868 mL | 14,786.76 mg |
| 4 tsp | 19.7157 mL | 19,715.69 mg |
| 5 tsp | 24.6446 mL | 24,644.61 mg |
| 6 tsp | 29.5735 mL | 29,573.53 mg |
| 8 tsp | 39.4314 mL | 39,431.37 mg |
| 10 tsp | 49.2892 mL | 49,289.22 mg |
| 12 tsp | 59.1471 mL | 59,147.06 mg |
| 16 tsp | 78.8627 mL | 78,862.75 mg |
A teaspoon measures volume. A US teaspoon is 4.92892159375 mL; a metric teaspoon is 5 mL.
A milligram measures mass. One thousand milligrams equal one gram.
There is no universal number because the answer depends on density and the teaspoon definition.
1 US tsp of water is approximately 4,928.92 mg1 metric tsp of water is 5,000 mgThese values are for water at approximately 1.000 g/mL using US teaspoons.
Divide milligrams by the milliliters in the chosen teaspoon, the density, and 1000.
Switch to Milligrams to TeaspoonsThe same teaspoon volume can contain a different mass when substances have different densities.
1 US tsp = 4.92892159375 mL1 metric tsp = 5 mLThe small difference changes the calculated mass.
| Unit | Symbol | Measures |
|---|---|---|
| Teaspoon (tsp) | tsp | Volume |
| Milliliters | mL | Volume |
| Milligram (mg) | mg | Mass |
Teaspoons and milliliters are volume units. Converting either one to milligrams requires density.
The calculator's unit definitions and notation are checked against official measurement guidance:
There is no universal answer. You need the substance density and the teaspoon definition.
Only when density is known because teaspoons measure volume and milligrams measure mass.
At approximately 1.000 g/mL, 1 US teaspoon of water is about 4,928.92 mg.
At approximately 1.000 g/mL, 1 metric teaspoon of water is 5,000 mg.
Density states how much mass is present in a given volume, so it links teaspoons to milligrams.
No. Teaspoons measure volume; milligrams measure mass.
Both measure volume. One US tsp is 4.92892159375 mL and one metric tsp is 5 mL.
A milligram measures mass and a milliliter measures volume. Density connects them.
Divide mg by the teaspoon volume in mL, density in g/mL, and 1000.
No. Different densities produce different masses for the same teaspoon volume.
Use a reliable density for the exact substance and conditions, expressed in g/mL.
You can enter bulk density, but powder density changes with packing, moisture, particle size, and measuring technique.
Ingredients vary by density, temperature, moisture, brand, and how tightly they are packed.
No. Use the medicine label concentration and qualified medical guidance rather than a generic density conversion.
A US teaspoon is 4.92892159375 mL; a metric teaspoon is exactly 5 mL.