What is the average number of grafts available?

The number of FUE grafts you can safely harvest without making the donor area look depleted depends on many factors such as: (1) your donor hair density, (2) how long you keep your donor hair, (3) how your body heals/scars, (4) contrast between your hair and skin, (5) hair texture/character, etc.
If you keep your donor hair buzzed short, even a 2000 graft FUE can make the back of your head look very thin.

With every patient having a different quality and density in the donor area there is no exact number on the maximum number of grafts you can extract without over harvesting.At our clinic an average procedure is usually around 2,000 grafts. If the patient were to repeat a second procedure we would probably extract another 1,500. If donor permits we could do at third procedure at around 800 grafts. Give or take the maximum average number of grafts would be around 4,000.Again this will vary from patient to patient.

The average amount of grafts available for a hair transplant would be roughly 4000 grafts without the area starting to look thin. This will always be different on a case per case basis and will need to be determined in your initial assessment. 

The capacity of the donor area to support an FUe procedure relates to the donor density measurements taken prior to having the surgery done. There are firm rules that should be honored. Speak with your surgeon