Each capsule has 1/4 teaspoon so you need only 1/2 teaspoon per day, EXCEPT if you have an illness like cancer, diabeter, or smoking. The difference with the extract is that it is heated and sometimes have fillers in them. Taking the fresh seeds assure you of getting the purest form.
I was given some grape seed capsules one time from the pharmacy and it had little or no affect on me at all. I have done it this way and was able to eliminate my taking of glucosamine sulfate for my knees.
Many web sites tell you to take the extract as the seeds are very difficult to obtain. Take a search on the net and you will literally find hundreds of sites wanting to buy seeds.