The protein density of a protein powder depends on the type of protein source used, the processing method, and the product's ingredients. Generally, whey protein is considered one of the highest protein density protein powders with a protein content ranging from 70-80% per serving. Egg protein and pea protein are also considered high protein density protein powders with a protein content of around 80% per serving. However, it is important to note that the protein density is not the only factor to consider when choosing a protein powder. Other factors such as the quality of the protein source, the presence of other nutrients, and the taste and texture of the powder are also important to consider. It is best to choose a protein powder based on your specific needs, preferences, and dietary restrictions.