Best Answer: It really depends on the brand of tea. While a teaspoon is a set measurement, a tea bag can be any size. On average, a tea bag has 2 teaspoons of loose tea inside. But some high quality tea can have 3 from what I've tried. 20 bags equals 1.5 ounces so about half to a third teaspoons. Tea bags use mechanicly produced tea that is almost powdered so that there is more surface area. You need more Fresh tea to brew loose leaf. If you are asking because you want to know how much loose tea to use one teaspoon per cup (some people say one per cup PLUS one for the pot.