Free tool

Graft calculator: what you’d need vs what you have

Most graft calculators only tell you how many grafts you’d need. The real question is whether your donor area can supply them. This puts both side by side.

Your Norwood stage

Not sure? Pick the closest; you can change it and watch the result.

Donor density

Follicular units per cm² at the back of your head. If you don’t know, “Typical” is a fair starting point.

Hair thickness

Fine hair needs more grafts for the same look.

Your age
Grafts likely needed
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Estimated lifetime supply
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Planning estimate only: need is the typical range clinics quote for your stage, adjusted for hair thickness; supply is density × 150–200 cm² usable donor area × 25–35% safely extractable. It assumes your donor hair is permanent; if it’s thinning (DUPA), supply can be far lower.

How the calculator works

Grafts needed uses the typical ranges clinics quote for each Norwood stage, adjusted for hair thickness (fine hair ×1.2, coarse ×0.85, rough adjustments, since fine hair covers less scalp per graft). Supply uses the standard planning formula: donor density × usable donor area × the share that can be safely removed over a lifetime. More detail in how many grafts do I have? and grafts by Norwood stage.

Norwood stageTypical grafts quoted
2500–1,000
31,000–2,000
3 Vertex1,500–2,500
42,000–3,000
53,000–4,000
64,000–5,500
75,000–7,000+
Donor density (FU/cm²)Estimated lifetime supply
55 (low)about 2,050–3,850
75 (typical)about 2,800–5,250
90 (high)about 3,400–6,300

The number that matters most

Donor density swings the supply estimate more than anything else, and most people have no idea what theirs is. The other unknown is whether your donor hair is genuinely permanent: if it’s thinning, the safe supply shrinks dramatically. Both are measurable under magnification before you ever book a consultation.

Replace “typical” with your own numbers

GraftReport’s donor check measures your donor hair’s thickness and evenness zone by zone and flags edges that are already thinning, so you know which row of this table you’re in.

Get the kit — $199

Common questions

How many grafts do I have?

A common estimate is donor density times usable donor area times the share that can be safely removed. With typical density (about 75 follicular units per cm²), a usable area of 150 to 200 cm² and 25 to 35% extractable, that is roughly 2,800 to 5,250 grafts over a lifetime.

How accurate is a graft calculator?

It gives a planning range, not a surgical plan. The biggest unknowns are your real donor density and whether your donor hair is permanent. A surgeon examining your scalp will refine every number.

Why does hair thickness change the number of grafts I need?

Coverage depends on each hair’s cross-section, which scales with the square of its width. Fine hair covers less scalp per graft, so more grafts are needed for the same look; coarse hair needs fewer.

What if I need more grafts than I have?

That is common at Norwood 6 to 7. Options include restoring the front only, adding beard or body hair, and medical treatment to slow further loss. Discuss them with a hair restoration surgeon.

Estimates only, for planning and education. Not medical advice or a surgical plan; a hair restoration surgeon must examine your scalp.