1,000 i.u. Pure vitamin D3 oil 1000 i.u. per drop in an MCT oil base. This vitamin D3 is a high grade D3 in an MCT (medium chain triglyceride) oil base derived from coconut oil. The most common form of vitamin D3 oil is a cheap corn oil or olive oil base both of which tend to go rancid easily. MCT oil has a natural resistance to rancidity and virtually never goes rancid except under extreme conditions. There are approximately 1,200 drops per one ounce bottle.Also available in 5000 i.u. per drop.