You will need: (for our family of five, I use the following amounts which make two travel-size containers I purchased from Wal-Mart; adjust accordingly for your needs)
I use about 1/4 - 1/2 tsp to brush my teeth. I love the way it cleans and polishes my teeth. I've noticed that I have less plaque build up than with conventional toothpastes I've used in the past. In addition, my hygienist has even noticed cleaner teeth and less time she spends on my mouth. Score!