Last Updated: November 2, 2026
The Altcoin Season Index measures how many of the largest cryptocurrencies have beaten Bitcoin over the past 90 days, on a scale of 0 to 100. A reading of 75 or more means it is altcoin season, 25 or less means Bitcoin season, and anything in between is a neutral market. It is not altcoin season in November 2026: CoinMarketCap’s index read 47 and Blockchaincenter’s original index 39 on November 2, and the last altcoin season ended in September 2025.
While Bitcoin (BTC) has long dominated the crypto market, altcoins such as Ethereum (ETH) go through periods when they rise much faster. The Altcoin Season Index tracks these swings and helps traders and investors see which side of the market is leading. This guide explains how the index works, where it stands today, when past altcoin seasons happened and how long they lasted, and the signs traders watch for the next one.
Is It Altcoin Season Now?
No. On November 2, 2026, both versions of the index sat in neutral territory, far below the 75 that marks an altcoin season, and the related market measures pointed the same way.
| Indicator | Reading on November 2, 2026 | What it shows |
|---|---|---|
| CoinMarketCap Altcoin Season Index | 47 out of 100 | 47 of the other 99 coins in its top 100 beat Bitcoin over 90 days |
| Blockchaincenter Altcoin Season Index | 39 out of 100 | 19 of the 49 altcoins in its top 50 beat Bitcoin over 90 days |
| Bitcoin dominance (CoinMarketCap) | About 60.0% | Bitcoin’s share of the crypto market, close to its 2026 high |
| ETH/BTC | About 0.0293 | Level with Bitcoin over 90 days, down about 8% over 30 days |
| Altcoin market cap (CoinMarketCap) | About $1.03 trillion | Down about 13% in a month and about 42% below its October 7, 2025 high |
Sources: CoinMarketCap and Blockchaincenter, read at about 18:00 UTC on November 2, 2026. ETH/BTC is our calculation from CoinMarketCap prices.
CoinMarketCap’s reading has slipped from this year’s high of 64 on September 27 and from 53 a week earlier, as most altcoins fell harder than Bitcoin through October, including after the October 29 Binance hack. Bitcoin gained about 20% over the 90-day window, so altcoins had to rise even faster to count, and only 47 did. The leaders were Quant, up more than 230%, followed by Raydium, Stacks, Zcash and NEAR Protocol, while 21 of the top 100 coins were down over the period, according to CoinMarketCap.
For CoinMarketCap’s index to reach 75, about 74 of those 99 coins would have to beat Bitcoin, 27 more than today. Its last reading at that level came on September 20, 2025, and Blockchaincenter’s on September 26, 2025.
Understanding the Altcoin Season Index
The Altcoin Season Index tracks the performance of altcoins relative to Bitcoin. It does not compare market capitalizations, as is sometimes assumed. Instead, it counts how many of the largest coins have risen more, or fallen less, than Bitcoin over a rolling 90-day window, and turns that share into a score from 0 to 100.
Two versions are widely cited. The original comes from Blockchaincenter.net, whose daily history starts in 2017 and which compares the top 50 coins. CoinMarketCap publishes a version based on the top 100 coins ranked on its site at the end of each day, refreshed daily. Both leave out stablecoins such as Tether and DAI and asset-backed or wrapped tokens such as WBTC and stETH, and both count Ethereum as an altcoin. The formula is:
Altcoin Season Index = (number of coins in the set that outperformed Bitcoin over the last 90 days / number of coins in the set, excluding Bitcoin) × 100
Interpretation:
- 75 or higher: Altcoin Season, at least three quarters of the coins have beaten Bitcoin
- 25 or lower: Bitcoin Season, a quarter or fewer have beaten Bitcoin
- 26 to 74: Neutral market phase, neither side clearly leads
A high reading means altcoins are broadly outperforming Bitcoin, while a low reading means Bitcoin is leading. Because every coin counts equally, the index measures how broad a move is, not how large: a coin that beats Bitcoin by 1% counts the same as one that beats it by 200%.
What Is an Altcoin?
An altcoin, short for “alternative coin,” is any cryptocurrency other than Bitcoin, the first cryptocurrency, which launched in January 2009. CoinMarketCap listed 40,111 cryptocurrencies on November 2, 2026, 8,050 of them active. Altcoins differ from Bitcoin in design and purpose. Bitcoin’s supply is capped at 21 million coins, and it is used mainly as a store of value and for payments. Ethereum, the largest altcoin with about 10.7% of the crypto market, runs smart contracts and decentralized apps and has no maximum supply. Stablecoins such as USDT track the US dollar, and thousands of smaller tokens serve specific networks, apps or communities. Most altcoins are smaller, less liquid and more volatile than Bitcoin, which is why they tend to rise faster in rallies and fall harder in selloffs. Our glossary entry on altcoins covers the main types.
Interpreting the ASI Chart
The ASI chart shows how the index has changed over time. Traders and analysts use it to see which side of the market is leading and for how long. Here are the key points to consider when reading it:
1. Altcoin Seasons vs. Bitcoin Dominance
A reading of 75 or more signals that altcoins are broadly outperforming Bitcoin, which is what traders call an “altcoin season.” These periods have usually come with a sharp fall in Bitcoin dominance, Bitcoin’s share of the total crypto market: dominance dropped to about 33% in January 2018 and to about 40% in May 2021, both during long altcoin seasons. A low reading means Bitcoin is leading, often when investors turn cautious or when new money is concentrated in Bitcoin, as with the spot Bitcoin ETFs since 2024. In November 2026, dominance near 60% and an index in the 40s describe a market that Bitcoin still leads.
2. Cycles and Trends
The chart shows the cyclical nature of the crypto market, and how short altcoin seasons are compared with the phases between them. Blockchaincenter’s 90-day index has spent 416 days at 75 or above since April 2017, against 956 days at 25 or below, out of about 3,500 days of data. In 2026 the index has stayed mostly neutral: CoinMarketCap’s reading ranged from 20 on January 1 to 64 on September 27, and Blockchaincenter’s from 22 on May 15 to 67 on August 2. A trend that builds over several weeks tells traders more than a single day’s reading.
3. Market Sentiment and Risk Appetite
A rising index usually reflects a growing appetite for risk, as investors move from Bitcoin into smaller coins they see as having more upside. A falling index suggests a more cautious market in which investors prefer Bitcoin, stablecoins or cash. Sentiment gauges agree today: the Crypto Fear and Greed Index from Alternative.me read 37, Fear, on November 2, 2026, after 30 on October 31 and 34 on November 1. Our crypto fear and greed index page explains how that gauge works. Regulation, interest rate decisions and shocks such as exchange hacks can shift sentiment and the index together.
4. Signs That Altcoin Season Is Beginning or Ending
Because the index looks back 90 days, it confirms an altcoin season after it has started rather than predicting one. Traders therefore watch faster signals alongside it:
- Bitcoin dominance (BTC.D): a sustained fall while the total market rises suggests money is rotating into altcoins; a rebound often marks the end of a season.
- ETH/BTC: Ether usually moves before smaller altcoins, so a rising ratio is read as an early sign of rotation. It stood at about 0.0293 on November 2, 2026, down about 8% over 30 days and about 16% over a year.
- TOTAL2 and TOTAL3: these TradingView series track the market value of the top 125 coins excluding Bitcoin, and excluding both Bitcoin and Ether. An altcoin season needs them rising in dollar terms, not just gaining share.
- OTHERS and OTHERS.D: OTHERS tracks the value of coins outside the top 10 and OTHERS.D their share of the market. These smaller coins tend to move last and fastest.
- Breadth: gains spreading across many coins and sectors rather than one narrative, and the index itself climbing toward 75.
Signs of an ending are the reverse: dominance turning up, ETH/BTC falling, gains narrowing to a few tokens and the index dropping back below 75. After the September 2025 season, CoinMarketCap’s reading was down to 35 by October 10.
5. How to Track the Altcoin Season Index
Both indexes are free. CoinMarketCap’s Altcoin Season Index page shows the current reading with yesterday’s, last week’s and last month’s values, the yearly high and low, a chart that can switch to the altcoin market cap, and the 90-day performance of every coin in its top 100. Blockchaincenter’s index adds 30-day and 365-day versions, a calendar that colors every day since 2017 by season, and statistics on past seasons. To track it effectively, compare the same source over time, note the time of each reading because values can change during the day, and check dominance and ETH/BTC alongside it. Our Bitcoin dominance page and daily crypto market today report follow these numbers.
When Was the Last Altcoin Season, and How Long Do They Last?
The last altcoin season was in September 2025. Blockchaincenter’s index stayed at 75 or above from September 11 to 21, 2025, peaking at 80, and touched 76 again on September 26. CoinMarketCap’s index was above the line for only three days, from September 18 to 20, with a peak of 78. Before that, both indexes showed a one-week altcoin season in early December 2024, peaking on December 4 at 88 on Blockchaincenter and 87 on CoinMarketCap.
| Period | Length | Peak reading |
|---|---|---|
| April 3 to July 28, 2017 | 117 days | 100 |
| January 6 to March 17, 2018 | 71 days | 100 |
| August 9 to September 4, 2020 | 27 days | 89 |
| March 25 to June 20, 2021 | 88 days | 98 |
| August 9 to September 14, 2022 | 37 days | 98 |
| January 22 to 29, 2024 | 8 days | 84 |
| December 2 to 8, 2024 | 7 days | 88 |
| September 11 to 21, 2025 | 11 days | 80 |
Source: Blockchaincenter’s daily 90-day index; periods of a week or longer at 75 or above, by our count. The 2017 period is counted from April 3, 2017, the first day of the 90-day data.
Most altcoin seasons are short. Blockchaincenter has recorded 25 since 2017, lasting about 17 days on average, and half lasted four days or less. The long seasons of 71 to 117 days came during the bull markets of 2017 to early 2018 and 2021; CoinMarketCap says large-cap altcoins returned 174% against Bitcoin’s 2% in its February to May 2021 season. Since 2022, none has lasted longer than 37 days. The current gap, which began after September 26, 2025, reached 402 days on November 2, 2026, second only to the 486 days between September 2022 and January 2024.
Implications for Traders and Investors
Traders use the index to judge the market regime rather than to pick coins. The approaches below are common practice, not recommendations, and none of them removes the risk of losses.
1. Timing Investments
Some traders treat a rising index together with falling Bitcoin dominance as a cue to add altcoin exposure, and a very high or falling reading as a cue to take profits. Because the index lags, many read 75 or more as confirmation that a season is under way rather than as an entry signal, and look to ETH/BTC and dominance for earlier clues. Seasons can also be brief: CoinMarketCap’s index stayed at 75 or above for only three days in September 2025.
2. Portfolio Diversification
Investors who hold both Bitcoin and altcoins sometimes shift the mix as the regime changes, for example by holding more Bitcoin or stablecoins in Bitcoin-led phases. The index does not say which altcoins will lead, and results vary widely: in the 90 days to November 2, 2026, Quant gained more than 230% while 21 of the top 100 coins fell, according to CoinMarketCap. Our top altcoins to watch list follows coins with dated catalysts, and the emerging altcoins radar covers new listings, token unlocks and red flags.
3. Risk Management
Altcoins are usually more volatile and less liquid than Bitcoin, so common risk controls include smaller position sizes, staggered entries and exits, stop-loss orders and avoiding leverage. Altcoins also tend to fall hardest when the cycle turns. CoinMarketCap’s altcoin market cap, which covers every coin except Bitcoin, stood at about $1.79 trillion on October 7, 2025, its highest daily reading since the index data begin in March 2024, and at about $1.03 trillion on November 2, 2026, roughly 42% lower. The index is only one input among many.
Limitations of the ASI
Despite its usefulness, the Altcoin Season Index has several limitations that investors should be aware of.
1. Data Interpretation
The two main indexes use different coin sets, so they rarely give the same number. On November 2, 2026, CoinMarketCap’s top-100 version read 47 and Blockchaincenter’s top-50 version 39, and in September 2025 Blockchaincenter’s index signaled an altcoin season a week before CoinMarketCap’s did. Because every coin counts equally, a rally led by a few large coins can leave the index low, while many small coins edging past Bitcoin can push it high. Use it together with Bitcoin dominance, ETH/BTC and market cap charts.
2. Volatility
Crypto prices move fast, and the index can jump by several points in a day as coins cross Bitcoin’s 90-day return. CoinMarketCap’s reading fell from 59 on October 28, 2026, to 42 the next day and was back at 53 on October 30. Brief spikes can also mislead: seven of Blockchaincenter’s 25 altcoin seasons since 2017 lasted a single day.
3. Market Influence
External events such as regulation, interest rate decisions and exchange failures hit Bitcoin and altcoins at the same time and can distort the index for weeks. The rolling window adds its own effect: when a big rally or crash from more than 90 days ago drops out of the calculation, the reading can change even if prices barely move that day. The window also makes the index slow. It confirmed the September 2025 altcoin season only after Bitcoin dominance had already fallen from about 65% in late June to about 57% in mid-September.
Conclusion
The Altcoin Season Index is a simple way to see whether altcoins or Bitcoin are leading the crypto market: a reading of 75 or more marks an altcoin season. As of November 2, 2026, it is not altcoin season. Both indexes are neutral, Bitcoin dominance is near 60%, and the last altcoin season ended in September 2025 after less than two weeks.
The index is a lagging, equal-weighted measure, so it works best alongside Bitcoin dominance, ETH/BTC and the TOTAL2 and OTHERS charts, and it should not be the only basis for an investment decision. The crypto market is volatile, so thorough research and careful risk management matter more than any single indicator.
This article is for informational purposes only and does not constitute financial advice.
Frequently Asked Questions
What is altcoin season?
Altcoin season is a period when most large cryptocurrencies other than Bitcoin rise faster than Bitcoin. The usual test is the Altcoin Season Index: if at least 75% of the top coins, excluding stablecoins and wrapped tokens, have beaten Bitcoin over the past 90 days, it is altcoin season. These periods usually come with falling Bitcoin dominance and a strong appetite for risk.
What is the Altcoin Season Index?
The Altcoin Season Index is a score from 0 to 100 that shows how many of the largest cryptocurrencies have outperformed Bitcoin over the past 90 days. Blockchaincenter publishes the original version, based on the top 50 coins, and CoinMarketCap a version based on the top 100. Readings of 75 or more mean altcoin season, and readings of 25 or less mean Bitcoin season.
How is the Altcoin Season Index calculated?
Each day, the index compares the 90-day price change of every coin in its set with Bitcoin’s, divides the number of coins that did better by the number compared and multiplies the result by 100. Stablecoins and asset-backed tokens such as WBTC are excluded. A result of 75 or higher signals altcoin season, 25 or lower Bitcoin season, and 26 to 74 a neutral market.
Is it altcoin season right now?
No. On November 2, 2026, CoinMarketCap’s Altcoin Season Index read 47 and Blockchaincenter’s 39, both neutral readings well below the 75 that marks an altcoin season. Bitcoin dominance was about 60%, near its 2026 high, and Ether had lost about 8% against Bitcoin over 30 days. Neither index has shown an altcoin season since September 2025.
When was the last altcoin season?
The last altcoin season was in September 2025. Blockchaincenter’s index was at 75 or higher from September 11 to 21 and again on September 26, peaking at 80, while CoinMarketCap’s was at 75 or above only from September 18 to 20. Before that, both showed a week-long altcoin season in early December 2024. The last one longer than two months ran from March to June 2021.
How long does altcoin season last?
Usually not long. Blockchaincenter has recorded 25 altcoin seasons since 2017, lasting about 17 days on average, and half of them lasted four days or less. The longest came during big bull markets: 117 days in 2017, 88 days from March to June 2021 and 71 days in early 2018. Since 2022 none has lasted more than 37 days, and the September 2025 season lasted 11 days.
When will altcoin season start?
No one can predict the date. The index needs at least 75% of top coins to beat Bitcoin over 90 days; on CoinMarketCap’s measure, that means about 74 of 99 coins, against 47 on November 2, 2026. Traders watch for Bitcoin dominance falling while the market rises, a rising ETH/BTC ratio and gains spreading across many altcoins as the first signs of a new season.
What are the signs that altcoin season is beginning or ending?
Signs of a beginning include Bitcoin dominance falling while the total market rises, a rising ETH/BTC ratio, TradingView’s TOTAL2 and OTHERS charts climbing in dollar terms and gains spreading across many coins. Signs of an ending are the reverse: dominance turning up, ETH/BTC weakening, gains narrowing to a few tokens and the Altcoin Season Index falling back below 75.
How can I track the Altcoin Season Index effectively?
Check the free index pages on CoinMarketCap and Blockchaincenter, which show the current reading, recent history and the yearly high and low. Compare the same source over time, because the two use different coin sets, and note the time of each reading, since values can move during the day. Follow Bitcoin dominance, ETH/BTC and the TOTAL2 and OTHERS charts alongside it.
What exactly is an altcoin and how does it differ from Bitcoin?
An altcoin is any cryptocurrency other than Bitcoin, from Ethereum, the largest, to stablecoins and thousands of smaller tokens. Bitcoin has a fixed supply of 21 million coins and is used mainly as a store of value. Many altcoins add features such as smart contracts, follow different supply rules or track the US dollar, and most are more volatile than Bitcoin.
What strategies do traders use for buying and selling altcoins?
Common approaches include waiting for falling Bitcoin dominance and a rising ETH/BTC ratio before adding altcoins, treating an index reading of 75 as confirmation rather than an entry signal, buying and selling in stages, keeping positions small, using stop-loss orders and avoiding leverage. Some take profits as gains narrow to a few coins. None of these methods guarantees results or removes the risk of losses.
What are the limitations of the Altcoin Season Index?
The index looks back 90 days, so it confirms trends late, and it counts every coin equally, so it shows how broad a move is rather than how large. Its versions use different coin sets and can disagree, as CoinMarketCap’s 47 and Blockchaincenter’s 39 did on November 2, 2026. It should never be the only basis for an investment decision.
Data sources: CoinMarketCap (Altcoin Season Index readings, its history since March 2024 and 90-day coin performance, altcoin market cap, Bitcoin and Ethereum dominance, ETH and BTC prices and coin counts, November 2, 2026), Blockchaincenter.net (Altcoin Season Index readings, daily history since 2017 and season statistics, November 2, 2026), TradingView (definitions of TOTAL2, TOTAL3, OTHERS and dominance symbols), Alternative.me (Crypto Fear and Greed Index) and our Bitcoin dominance page (historical dominance from CoinMarketCap). Season lengths and gaps are our own count from Blockchaincenter’s daily data.
About the author
Mushumir Butt is a seasoned crypto journalist with over three years of experience reporting on the world of blockchain and cryptocurrency. At Blockchain Reporter, he delivers insightful news, in‐depth project reviews, and precise price analysis and predictions. With a strong background in SEO and digital marketing, Mushumir excels at breaking down complex trends into clear, accessible content, ensuring readers stay ahead in the fast‐paced crypto space.
