Graft Calculation | Hair Transplantation in Austria

Graft Calculation

There are between 180-200 hair roots per square centimetre in a normal scalp. The aim in hair transplantation is to achieve this number. If the hairless area is large, 40-50 % less than this number can be implanted. This is because baldness occurs when about 50% of hair volume is lost. If the loss is more than 50%, baldness can be clearly seen.

The reason why numbers are not clear in these calculations is that the structure of hair strands differs from person to person. Depending on hair structure the visibility of the skin underneath increases or decreases.

Thick hair is more advantageous than fine hair.
Curly hair is more advantageous than straight hair.
Light-coloured hair, for example, greying hair, is more advantageous than black hair.

According to the information above, a minimum of 100 hair roots and a maximum of 200 hair roots must be transplanted to one square centimetre in a completely hairless area. Additionally, it is important to know that the number of hair roots and the number of grafts are two different things. Based on the information above, there are on average 2 hair roots in grafts collected by the most commonly used 0.7-0.75 mm FUE needles (punch). Thus, for transplantation a minimum of 50 grafts and a maximum of 100 grafts are needed per square centimetre on average.

In the video below, you can see how the area with hair loss is calculated and you can also roughly calculate how many grafts you need with our graft calculation software.

Area and graft calculation in hair transplantation

1^st Stage

First, identify the areas where you have hair loss by clicking on the marked locations on the pictures. The areas that you click will be darkened. If you mark the wrong places, they will go back to their old state if you click on the same place a second time and pull back the cursor.

2^nd Stage

Click and hold down the horizontal marker below the pictures marking how many grafts per square centimetre you want and drag it to the right from zero to 10, 20, 30, 45 or any range you want. 20 grafts per square centimetre indicate sparse transplantation, whereas 20-40 grafts indicate moderate density transplantation and a number of grafts over 40-45 indicate dense transplantation.

3^rd Stage

Finally, click on "calculate" to see the total number of grafts and hair roots needed. The number below "#of grafts" gives you the number of grafts that need to be transplanted and the number below "#of hairs" gives you the number of hair roots that need to be transplanted.

Important note: The graft calculation software is designed for a 0.9-1 mm FUE tip. With micro FUE, smaller grafts are collected with fine tips and denser transplantation is done. For example, about 20-30% more grafts than the software result should be calculated for grafts that are collected with a 0.7 mm FUE needle.