1500 FUE hair graft enough? I'm 26. (photos)

Photos cannot determine if you would be a good candidate for surgery.  You need an examination and the doctor needs to understand your goals and expectations.
You need to have good communication with your doctor to understand what your end result will look like. 
Someone with your hair loss pattern may be perfectly happy with 1500 grafts, while others may not be happy even with over 3000 grafts.  You also have to realize one surgery may not be enough.  To add to the confusion, straight black hair on fair skin results in a thinner appearing outcome then someone with curly blond hair on fair skin.   I hope you can appreciate there are many factors to your end result than just a "number" of grafts.

1,500 grafts would not be enough to cover the area you highlited at full density. I suggest having additional consultation s to see what other doctors suggest.Often you can submit photos to top hair restoration surgeons for a complimentary evaluation. This should help lead you in the right direction. Having multiple consultations with different doctors cannot hurt. 

If you are interested in filling the area you outlined (plus keeping with a mature hairline), in the photo which includes hairline, front and some of the top, I would suggest starting with 2000 to 2500.  If you go below the 2000 then the density in the front would be too low and you would see "show through scalp". Let me preference this by saying these numbers depend on the characteristics of your donor area which include the thickness/coarseness of your hair, and the donor density. That is why we offer up a range rather than a specific number.

Depending upon the thickness of your hair (fine, medium or coarse) I would think that the range of grafts for high density should be betwen 1800-2300 grafts, the lower number for coarser hair. Of course you need the donor density if you are going to have FUE which must be measured for determining your donor site depletion after the first hair transplant.