Teaspoon (tsp) to Millilitre (ml)
Converting teaspoons to millilitres is straightforward: 1 teaspoon equals 5 ml in the UK metric system. This is the standard used in British recipes and on medicine packaging. American teaspoons are marginally smaller at 4.929 ml, but the difference is negligible in most cooking contexts. Teaspoons are essential for measuring small quantities of spices, baking powder, and flavourings.
Frequently asked questions
In the UK, 1 teaspoon equals 5 ml. This is the metric teaspoon used in British recipes and on medicine dosage labels. The US teaspoon is 4.929 ml — slightly smaller, though the difference rarely matters in everyday cooking.
Three teaspoons equal 3 × 5 ml = 15 ml, which is exactly 1 tablespoon. This relationship — 3 teaspoons to 1 tablespoon — is one of the most useful conversions to memorise in the kitchen.
One tablespoon equals exactly 3 teaspoons, or 15 ml. So a teaspoon is one-third of a tablespoon. If a recipe calls for a tablespoon and you only have a teaspoon measure, simply fill it three times.
Small inaccuracies in leavening agents such as baking powder or bicarbonate of soda can significantly affect results. Too much can cause a bitter flavour or collapse; too little and the bake will not rise properly. Always level off the spoon with a straight edge for consistent results.