How many is 20 ml in teaspoon?

To convert milliliters (ml) to teaspoons (tsp), you can use the following conversion factor:

1 teaspoon (tsp) = 4.92892 milliliters (ml)

Therefore, to convert 20 ml to teaspoons, you would divide 20 ml by 4.92892 ml/tsp:

20 ml / 4.92892 ml/tsp ≈ 4.057 tsp

So, 20 ml is approximately equal to 4.057 teaspoons.