The Altcoin Season Index in March 2025 is 21 according to CoinMarketCap data, clearly indicating Bitcoin's dominance in the current market phase. This result means that most major alternative coins have underperformed Bitcoin in returns over the past 90 days. Below, we explain the index methodology, the current market picture, and what this means for mining practices.
What is the Altcoin Season Index?
The Altcoin Season Index is a quantitative indicator that shows the share of major altcoins that have outperformed Bitcoin in returns over a selected period. Essentially, the index is expressed as a percentage: the ratio of the number of top 100 coins that have outpaced Bitcoin to the total number of assets considered. A value of 75 or higher formally declares an 'altcoin season', while the current 21 marks a 'Bitcoin season'.
How is the Altcoin Season Index calculated?
The CoinMarketCap algorithm analyzes the 90-day performance of the top 100 cryptocurrencies, excluding stablecoins and wrapped tokens to avoid distorting the picture of speculative returns. Each coin is compared to Bitcoin over the same period, and the final percentage reflects the share of those that showed better results. This approach makes the index more resilient to short-term spikes, as the 90-day window smooths out volatility.
Current situation in the cryptocurrency market
With the current value of 21, the market is in a phase where Bitcoin maintains leadership in returns relative to most major altcoins. The source text notes that such periods often precede future altcoin rallies, but the index itself is lagging and confirms trends only after they have formed. The discussion also mentions that events influencing investor attention toward Bitcoin amplify the 'Bitcoin season' effect.
What could change the situation?
Sustainable growth of the Altcoin Season Index to the 75 threshold usually requires a combination of factors: Bitcoin establishing new local highs, as well as strengthening positive narratives in sectors like DeFi, NFT, or GameFi. Additionally, shifts in market sentiment and capital inflows into altcoins can trigger rotation. It is important to remember that the index confirms an already established trend, so signals for change come from a combination of on-chain metrics and market events.
Why is this important?
For a miner with 1–1000 devices, it is important to know that the index at 21 reflects Bitcoin dominance, but by itself it does not provide direct guidance on the profitability of mining altcoins or Bitcoin. At the same time, the 'Bitcoin season' phase is often accompanied by capital shifting into the most liquid coin, which can affect spot prices and spreads during exchanges. Understanding the cycle helps build a long-term strategy for storing and selling mined coins, even if there is no direct impact on the mining process.
What to do?
Practical steps for a miner focused on the Russian market can be reduced to a few simple directions that help reduce risks and prepare for a possible market phase change:
- Check your portfolio structure: assess which coins you hold and their liquidity in local exchanges and pools.
- Consider partially taking profits on Bitcoin during strong short-term rallies and allocate proceeds between operational expenses and reserves.
- Monitor on-chain indicators and news in key sectors (DeFi, NFT, GameFi) — this will help spot potential capital rotation signals.
- Maintain technical readiness: update miner firmware and prepare space/power for possible increased load if altcoins become more profitable.
If you want to dive deeper into the index dynamics, check out the article about the recent index rise to 22 and its market context rose to 22, as well as the review featuring a selection of altcoins for 2025 best coins of 2025, where individual projects and their prospects are discussed. These materials will help better evaluate which altcoins might outperform Bitcoin in the future.