Convert tablespoons to teaspoons

tsp = tbsp × 3

• ¼ tbsp = ¾ tsp
• ½ tbsp = 1½ tsp
• 1 tbsp = 3 tsp
• 2 tbsp = 6 tsp
• 3 tbsp = 9 tsp

The 3-to-1 ratio is American and British. In Australia the standard tablespoon is 20 mL — four 5 mL teaspoons — not 15 mL. An Australian recipe asking for 1 tablespoon of baking powder, measured with an American spoon, comes out a quarter short.

Medication labels that say "teaspoon" mean exactly 5 mL, and household spoons are not that: a study of household teaspoons published in the Annals of Pharmacotherapy found capacities from about 2.5 to 7.3 mL. The American Academy of Pediatrics recommends dosing liquid medicine in millilitres with the syringe or cup that comes with it.

For millilitres, see tsp to mL.

NIST Special Publication 811, the US guide to the SI lists the US tablespoon as 14.78676 mL and the teaspoon as 4.928922 mL, exactly one third. The FDA's 21 CFR 101.9 rounds them to 15 mL and 5 mL for nutrition labels. Australian Standard measuring spoons are different: a 20 mL tablespoon and a 5 mL teaspoon.