Teaspoons to Milliliters Converter (tsp to mL)

The teaspoon is the small end of American measuring: baking soda, salt, vanilla and yeast in recipes, and sugar and salt in health advice. Three US teaspoons fill a US tablespoon, which puts one teaspoon at exactly 4.92892159375 mL; food labels and pharmacies round it to 5 mL.

Medicine is the one place to skip the kitchen spoon altogether: the FDA advises measuring a liquid medicine with the dosing cup or syringe that comes with it, because household spoons vary and teaspoons are easily confused with tablespoons. For cooking, the chart runs from ⅛ teaspoon up to 12 teaspoons, a quarter cup. Baking is where teaspoons count most, since small errors in baking soda, baking powder or salt show in the result, so level each spoon with a straight edge.

How to use this tool

1. Type a value in the Teaspoon box to see it in milliliters, or type in the Milliliter box to convert the other way.
2. Press ⇄ to swap the two units, or Load example for a typical value.
3. Check the charts below for common values; for other units, open the Volume converter.

Formula

Milliliter (mL) = Teaspoon (tsp) × 4.92892159375

Teaspoon (tsp) = Milliliter (mL) × 0.202884136211

Both factors come from exact definitions: 1 milliliter = 0.202884136211 teaspoons and 1 teaspoon = 4.92892159375 milliliters (shown to 12 significant digits).

Example

Two conversions worked with the same factors the converter uses:

2.25 tsp × 4.92892159375 ≈ 11.0901 mL

7.5 mL × 0.202884136211 ≈ 1.52163 tsp

Teaspoon to Milliliter chart

Common values from teaspoons to milliliters, rounded to four decimal places.

Milliliter to Teaspoon chart

The reverse direction for values people often look up.

Teaspoon amounts worth knowing

Quick mental estimate

Count 5 mL per teaspoon: 4 tsp → 20 mL, against an exact 19.72 mL. Rounding up to 5 overstates every teaspoon by about 1.4%, the same rounding food labels use.

Use the converter or the charts when the exact figure matters.

The two units

Teaspoon (tsp): The US customary teaspoon used here is one third of a US tablespoon, or 1/6 of a US fluid ounce: exactly 4.92892159375 mL. A metric teaspoon is 5 mL and uses a different convention.

Milliliter (mL): A milliliter is one thousandth of a liter and exactly the same volume as one cubic centimeter. There are 1,000 microliters in a milliliter and 1,000 milliliters in a liter.