Zebra Atlas

4,800 rare conditions and how rare each one is. Tap a name for its Orphanet entry.

How to read it. Most figures are prevalence: how many people have it at any one time. Some are new cases a year, rates at birth, or a count of reported cases where no rate exists. A region is shown when the only figure comes from one country or group, which can make a condition look commoner than it is worldwide. Many figures are bands (for example 1–9 in 100,000), shown as ranges.

Source. Orphanet, Orphadata rare disease epidemiology and classifications (data dated 23 Jun 2026), CC BY 4.0. Conditions with no usable figure are left out.