Google can do all kinds of unit conversions for you. In a Google search field, I just asked teaspoons in one tablespoon and got this: teaspoons in one tablespoon. There are 3 US teaspoons in one US tablespoon. (So, there are 1.5 teaspoons in half a US tablespoon. I have graduated measuring spoons that include half and quarter teaspoon measures.) Written Dec 28 • View Upvotes.