Learning Center
Norwood and Ludwig Scales: How Hair Loss Is Staged
The Norwood scale stages male pattern hair loss; the Ludwig scale stages female. Learn the stages and which ones laser devices are cleared for.
Dermatologists stage pattern hair loss with two scales. Knowing your stage helps you judge whether a laser device is likely to help — and most FDA clearances name specific stages in their indications for use.
Norwood scale (men)
| Stage | What it looks like |
|---|---|
| I | No visible recession |
| II | Slight recession at the temples — the "mature hairline" |
| III | Deeper temple recession; the first stage considered hair loss. IIIa adds early crown thinning |
| IV | Clear frontal recession plus a thinning crown, with a band of hair between |
| V | Frontal and crown areas enlarge; the band narrows |
| VI | Front and crown merge |
| VII | Only a horseshoe of hair remains at the sides and back |
Home laser devices are typically cleared for roughly Norwood IIa–V. VERIFY per device Beyond that, follicles in the bald areas are usually gone.
Ludwig scale (women)
| Stage | What it looks like |
|---|---|
| I | Mild thinning on top; the part widens slightly |
| II | Noticeable thinning across the crown; scalp visible through the hair |
| III | Extensive thinning on top with a see-through appearance; hairline usually kept |
Clearances for women typically cover Ludwig I–II. VERIFY per device
Using the scales to choose
- Early stages (Norwood II–III, Ludwig I): the best window for laser therapy. Follicles are miniaturised but alive.
- Mid stages (Norwood IV–V, Ludwig II): still within most clearances; expect slower, more modest change, especially at the hairline.
- Advanced stages: home devices are unlikely to help in smooth, bald areas. Talk to a dermatologist about other options.
Match your stage to a format in our best-for guides, or compare every device in the rankings hub.
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Results vary. Not a substitute for medical advice.