What is Altcoin?
Any cryptocurrency that isn't Bitcoin — from Ethereum down to coins minted this morning. A category so broad it needs sorting before it means anything.
"Altcoin" means any cryptocurrency that isn't Bitcoin — a definition that lumps Ethereum's trillion-dollar-class platform in with coins minted this morning, which tells you the word is a starting point rather than an analysis. The useful move is sorting: platform coins with real economies, stablecoins doing plumbing work, sector tokens tied to one application, and memecoins running on community and jokes.
The base rates deserve respect: thousands of altcoins are tracked, tens of millions of tokens have been created, and the overwhelming majority are dead or dying — while in rallies, the survivors can dramatically outrun Bitcoin. That rotation is measurable: our altseason index tracks daily what share of major altcoins are beating BTC. The full tour is in our altcoin explainer.
See it in practice
Related terms: Bitcoin · Memecoin · Market cap · full glossary
FAQ
Are altcoins riskier than Bitcoin?
As a class, decisively — smaller size means thinner liquidity, easier manipulation, and a far higher death rate. The further down the market-cap list, the more the odds resemble a lottery.
What is "altseason"?
A stretch where money rotates from Bitcoin into altcoins broadly, which then outperform. Our index measures it daily as the share of the top 50 coins beating BTC over 90 days.
General information only, not financial advice. Definitions are maintained in our fact database and reviewed with the daily rebuild.