An altcoin is any cryptocurrency other than Bitcoin. The word is a contraction of “alternative coins”, and with that the definition is already complete: there is Bitcoin, and there is everything else. How large this “everything else” is can be put in figures. On October 23, 2026 the alternatives stand for around $1.22 trillion, which is 42.62 percent of the entire crypto market of $2.86 trillion. Only 84 coins carry any notable weight, however, because that is how many clear one billion dollars at all.

That makes the term as useful as it is misleading. It sorts a market with thousands of entries into two drawers, one of which holds almost everything: stablecoins that are never meant to rise, platform tokens for smart contracts,…