Altcoin: any cryptocurrency that is not Bitcoin

Everything That Is Not Bitcoin

An altcoin is any cryptocurrency that is not Bitcoin. The term emerged in Bitcoin's early days when a handful of forks like Litecoin and Namecoin appeared as alternative coins. Today it covers tens of thousands of assets—from large-cap networks like Ethereum, Solana, and Cardano to niche tokens powering single applications.

The category is much too broad to be a useful investment signal. Ethereum is a programmable platform with billions in daily activity; a freshly launched memecoin with no team and a $50,000 market cap is also technically an altcoin. What unites them is only that they are not Bitcoin. Traders often subdivide further—Layer 1 platforms, Layer 2 scaling solutions, DeFi tokens, gaming and metaverse tokens, memecoins, and so on.

Altcoins have historically followed Bitcoin's cycle with amplified swings. When Bitcoin rallies, capital tends to rotate down the risk curve into altcoins, producing the periods traders call altseason. When Bitcoin falls, altcoins typically fall harder. The Bitcoin dominance metric—Bitcoin's share of total crypto market cap—is the simplest read on where in the cycle this rotation sits.