Holistic online has an easy and simple online test to determine your doshic constitution (prakruti). Click here to take it and find out what your natural balance of primal energies (doshas) is. The more in depth the questions are, the more accurate your doshic analysis is. This is why when you have an intake session with an ayurvedic healer (vaidhya), you would have a three hour discussion on every aspect of your life to determine your constitution and your imbalances. They also offer a second version that is a bit longer, which you can click here for.
Remember, when you are answering these questions, you should answer them from the perspective of the happiest you have been. This is because we are happiest when we are in our ideal balance of the doshas, and so to determine this ideal ratio, we should answer these questions from that viewpoint.
When you answer these surveys from the standpoint of where you are today, now, you are determining your vikruti (current state) instead of your prakruti. To access the survey for determining your vikruti, see the post "Step 2: what does a doshic imbalance mean?" in this category.