We launched our own Altcoin Season Index — here's how it's calculated

CryptoPulse.media has launched a new section — the Altcoin Season Index: our own calculation of what share of the top 100 cryptocurrencies by market cap are outperforming Bitcoin over the last 30 days. The index updates live, several times a day, and shows not a forecast but an actual read of where the market's capital is rotating right now.

Why Another Index

Traders have long used the term "altcoin season" for periods when most altcoins rise faster than Bitcoin itself — a signal that investors are willing to take on more risk in search of higher returns. The problem is that this rotation is hard to judge by eye: some coins rise, others fall, and a general market vibe is easy to mistake for actual statistics. Our index turns that vibe into a concrete number from 0 to 100.

How the Index Is Calculated

We take the top 100 cryptocurrencies by market cap on CoinGecko, excluding stablecoins (USDT, USDC, DAI, and similar — pegged to $1, so they can't meaningfully out- or under-perform) and wrapped/staked tokens (WBTC, wstETH, and similar — these technically track another asset's price). For each of the remaining coins, we compare its 30-day return to Bitcoin's return over the same period. The index is the percentage of coins that beat Bitcoin, rounded to a whole number.

• 0-25 — "Bitcoin Season": market capital concentrates in BTC
• 26-74 — "Neutral": no clear tilt in either direction
• 75-100 — "Altcoin Season": investors actively chase returns beyond Bitcoin — historically, such periods occurred in late 2017 and in 2021, both times near the peak of a market cycle

How It Differs From CoinMarketCap's Index

The methodology is similar — the share of top coins beating Bitcoin — but CoinMarketCap uses a 90-day window, while we use 30 days. That's not an error, it's a deliberate trade-off: CoinGecko returns 30-day performance for the entire top-100 list in a single request, whereas a 90-day history would require a separate API call per coin and would run into free-tier rate limits. Both windows measure the same underlying idea over different time horizons, so our index and CoinMarketCap's naturally won't show the same number on any given day.

What Else Is On the Page

Beyond the index value itself, the page shows leaderboards — the top 10 coins beating Bitcoin over 30 days, and the top 10 lagging behind — along with an FAQ section and links to our data sources and comparable methodologies. The index refreshes roughly three times a day from live CoinGecko prices.

See the current index reading and leaderboards here: cryptopulse.media/en/altcoin-season.

The Altcoin Season Index is a statistical tool, not a trading signal or investment advice. Past price performance does not guarantee future results.