Altseason Index
What it shows
The SHARE of top-market coins that outperformed Bitcoin over the last 90 days. 100 means "every counted coin beat BTC", 0 means "none did". Stablecoins are excluded (their return sits still by design), as are wrapped and liquid-staking tokens (the same exposure as the base asset counted twice). The widget also states plainly how many coins entered the sample and how many were skipped for lack of full history.
How to read it
Read the index as a summary of what has ALREADY happened over the last 90 days, and always alongside the sample size: 60 out of fifty coins says more about the market than 60 out of twenty. A high reading does not promise the altcoin season will last, and a low one does not promise it will not start; this describes the past. The chart below shows whether the index has been climbing for weeks or just jitters in place. This is not investment advice.
Parameters
- Index 0–100
- The share of sampled coins that beat Bitcoin over 90 days. Thresholds: 75+ is "altcoin season", 25 or less is "Bitcoin season", anything between is a mixed market. The thresholds are a market convention, not a law.
- Positive reading: A high reading says capital historically spread widely across the market, which does not mean it will stay that way.
- Negative reading: A low reading says Bitcoin held the edge while the rest of the market lagged.
- Sample and exclusions
- How many coins we actually counted, out of how many, how many were excluded as stablecoins or wrapped tokens, and how many were skipped for missing history. When the sample is too small we save nothing: the day stays a gap on the chart, never a zero.
- Bitcoin and median coin
- Bitcoin's 90-day return and the median return of the sampled coins. Putting the two side by side shows whether altcoin outperformance came from their strength or from BTC weakness.
- Strongest and weakest vs BTC
- Coins with the largest and smallest return gap versus Bitcoin over the same window. Clicking opens the project page with the rest of the data.
Example
The index reads 62 with a sample of 46 out of 50 coins, Bitcoin +8%, median coin +14%. Read it like this: over the last 90 days almost two thirds of the top coins did better than BTC, and the typical coin gained roughly twice what Bitcoin did. Four coins were skipped for missing history, that is why the sample is 46, not 50.