How to Use the Fear and Greed and Altcoin Season Indexes

Fear and Greed Index

The Fear and Greed Index scores market sentiment from 0 (extreme fear) to 100 (extreme greed). It combines five inputs, each compared with the past year:

• Bitcoin's 30-day volatility (25%)
• Bitcoin's price relative to its 90-day average (25%)
• The share of the top 100 coins above their own 30-day average (20%)
• The 30-day change in Bitcoin dominance (15%)
• Stablecoins' share of the total market (15%)

How people use it

The idea comes from a simple observation: crowds tend to buy after prices have risen and sell after they have fallen. Extreme fear has often coincided with good long-term entry points, and extreme greed with stretched markets. Some investors use it to pace regular purchases, buying a little more when fear is high.

Limits

Sentiment can stay extreme for weeks, and markets can keep falling in "extreme fear". The index describes the mood; it cannot time tops or bottoms.

Altcoin Season Index

The Altcoin Season Index counts how many of the 50 largest altcoins (excluding stablecoins and wrapped or staked tokens) beat Bitcoin over the last 90 days. At 75 or more it is altcoin season; at 25 or less, Bitcoin season.

How people use it

It tells you whether the market is rewarding broad risk-taking or concentrating in Bitcoin. In Bitcoin season, most altcoins lose value against BTC even when their dollar prices rise.

Limits

It looks backwards over 90 days, so it confirms a trend rather than predicting one, and a few very strong coins can mask weakness in the rest.

Reading them together

High greed with a rising altcoin index is a typical late-cycle pattern: broad speculation. Fear with Bitcoin season is a typical risk-off pattern. Neither is a signal on its own; use them as context alongside your own plan.