Altcoin Season Index slips to 57 as Bitcoin dominance climbs back above 60%
CoinMarketCap's gauge sits well below the 75 mark that signals altcoin season after peaking at 64 on September 27, while Bitcoin's market share rose to 60.1%.
PRICE ANALYSISALTCOINS
Hana Kimura
10/20/20261 min read
CoinMarketCap's Altcoin Season Index stood at 57 on October 20, down from 58 a day earlier, TokenPost reported. The reading was above 55 a week earlier and 50 a month earlier. The index set its yearly high of 64 on September 27 after bottoming at 14 on December 19, 2025. On October 1 it read 61, up from 23 a month before, according to Analytics Insight.
The index measures what share of the 100 largest altcoins, excluding stablecoins, outperformed Bitcoin over the previous 90 days. A reading of 25 or lower marks a Bitcoin season, while 75 or higher marks an altcoin season. At 57, more than half of large altcoins have beaten Bitcoin over the quarter, but the outperformance is not broad enough to meet the threshold.
Market share data points in the same direction. Bitcoin dominance rose to 60.1% from 59.4% a week earlier, while Ether's share slipped to 10.7% from 10.9% and the rest of the altcoin market fell to 29.2% from 29.7%. On October 1, Bitcoin dominance had stood at 58.6%.
In absolute terms, Bitcoin's market value was about $1.64 trillion against roughly $1.10 trillion for all altcoins combined. Altcoins carried more trading, however, with $43.13 billion in 24-hour volume compared with $23.17 billion for Bitcoin. Bitcoin traded at $81,433 on October 20, with a 90-day return of 23.23%.
Source: TokenPost, Analytics Insight.