Is the Altcoin Season Index Accurate? I Tested It Against Six Years of Data

By Josh Molnar · July 2026 · 5 min read

For years, one number has told crypto traders when altcoin season is arriving. It is called the Altcoin Season Index, and when it turns green the whole market repeats the same phrase. Altcoin season is here. I ran six years of data through it to find out if it actually works, and the most watched altcoin timing tool in crypto has been a coin flip the entire time.

What the Altcoin Season Index actually measures

The Altcoin Season Index has a simple rule. It looks at the top 50 coins and counts how many of them beat Bitcoin over the last 90 days. If enough of them did, it declares altcoin season. If Bitcoin led instead, it calls it Bitcoin season.

Read that definition one more time. The last 90 days. Everything the index knows is already in the past. It is a scoreboard for a race that has already been run.

The Altcoin Season Index plotted from 2019 to 2026 with the green altcoin-season zone marked near the top

The problem with a rear view mirror

Because the index only measures the last three months, it turns green after the move has already happened. By the time it flashes altcoin season, the rotation it is describing is roughly three months old. You are not early. You are late.

Look at what happened at the real altcoin peaks. Every time the market topped, the index was screaming altcoin season right as the smart money was selling into the excitement. The signal everyone waits for tends to light up at the exact moment the easy money is already gone.

The Altcoin Season Index next to the total altcoin market cap with red markers showing the index near its peak at every major cycle top

I put it to the only test that matters

A signal is only worth something if it tells you what happens next. So I asked one clean question. When the Altcoin Season Index says it is altcoin season, do altcoins actually go on to beat Bitcoin over the following month?

Across six years of data the answer is 50 percent. A coin flip. The single most popular altcoin timing tool in the market tells you nothing reliable about what comes next. It describes the past accurately and it predicts the future no better than chance.

Building something that looks forward

So I built my own. Instead of counting what altcoins have already done, it reads the forces that move capital between Bitcoin and the rest of the market and folds them into one live score from zero to one hundred. The exact recipe stays proprietary, but the idea is easy to state. Measure the pressure that leads a rotation, not the scoreboard that trails it. I called it the Altseason Radar.

How the Radar compares

I ran the Radar through the exact same test over the same six years. When it says altcoins are favored, they beat Bitcoin over the next month 59 percent of the time, and by a wider margin on the occasions it is right. That is not a coin flip. It is a real, measurable edge over the tool the entire market already trusts.

Bar chart comparing forward accuracy, the Altcoin Season Index at 50 percent versus the Altseason Radar at 59 percent, with a coin-flip reference line

The honest part

Fifty nine percent is not a crystal ball, and I am not going to pretend that it is. We may never see another true altcoin season the way people remember 2021. The Radar is a higher conviction read of the regime you are in right now, not a promise about the next one. But when the alternative is a literal coin flip, a 59 percent read is a meaningful upgrade. One tool describes the past. The other reads the road ahead.

See the Radar live

The Altseason Radar updates every day and it is completely free. You can watch it move on the Altseason Radar chart. If you would rather have the link sent straight to you, comment RADAR on the post and it will come to your inbox. No email, no catch.

I break down the data on Bitcoin and the altcoin market like this every day, free, on Instagram. To trade alongside me and the community, come to bitcoindaily.vip.

Educational, not financial advice. Every cycle is different and past performance is not a guarantee.

Common questions

Is the Altcoin Season Index accurate?

It is accurate at describing the past but not at predicting the future. It measures how many of the top 50 coins beat Bitcoin over the last 90 days. Over six years of data, when it flashed altcoin season, altcoins beat Bitcoin the next month only 50 percent of the time, which is a coin flip.

What is the Altcoin Season Index?

It is a gauge that counts how many of the top 50 coins outperformed Bitcoin over the trailing 90 days. A high reading is called altcoin season and a low reading is called Bitcoin season. It is backward looking by design.

Can you predict altcoin season?

Not reliably. Most altcoin timing signals fail once you test them out of sample. The Altseason Radar, which reads the forces that lead a rotation rather than trail it, hit 59 percent forward over six years. That beats the index, but it is still a probabilistic read and not a guarantee.

What is the Altseason Radar?

It is a free live indicator from Bitcoin Daily that scores from zero to one hundred whether the market favors Bitcoin or altcoins right now. It was built to beat the lagging Altcoin Season Index at its own job and to read what altcoins do next more accurately.

We break down the market like this every day, free on Instagram and YouTube, and in depth inside the community.

Education, not financial advice. Trading involves real risk.