Dominance
One asset's market capitalization expressed as a percentage of the combined market capitalization of all assets a provider tracks.
Bitcoin dominance is the common version, and it is used to describe how concentrated the market is in the largest asset. The denominator is the fragile part: it depends on how many assets the provider covers, whether stablecoins are included, and how each asset's circulating supply is estimated. Adding newly listed assets or removing delisted ones changes dominance without any price moving, which makes long histories of the series awkward to interpret. Read as a description of relative size within a defined universe, it is informative; read as a signal about a single asset, it conflates two different things.
In practice
A provider that expands coverage to thousands of small assets will show slightly lower bitcoin dominance than one tracking only the largest few hundred.
The common misunderstanding
A move in dominance is not necessarily about the leading asset; the ratio also shifts when coverage rules or supply estimates for everything else change.
The figure this maps to
An asset's market capitalization as a percentage of the total capitalization of all covered digital assets.
Limits: The denominator is an open-ended list that grows every time a new token is listed, so an asset's dominance can decline while nothing whatsoever changes about it. The total double counts systematically: wrapped bitcoin, staked-ether derivative tokens, and exchange-issued representations all add…