How this calculator works
One US customary teaspoon is exactly 1/768 of a US gallon, or 4.92892159375 mL. This differs from the 5 mL metric teaspoon. Use the definition in the recipe: the small difference becomes noticeable when scaling a large batch.
Formula
US tsp = mL / 4.92892159375; mL = US tsp x 4.92892159375. Metric tsp = mL / 5.
Worked example
A 10 mL measure equals about 2.028841362 US tsp, or exactly 2 metric teaspoons. A quarter of a US teaspoon is 1.2322303984375 mL.
Advertisement
Frequently asked questions
Is one teaspoon always 5 mL?
Only under the metric spoon convention. The US customary teaspoon is slightly smaller.
How many US teaspoons are in a US tablespoon?
Exactly three.
Can I use an ordinary eating spoon?
Its capacity is not standardised. A marked measuring spoon or a volume measure is needed to reproduce a specified quantity.