What RSI tells you

The Relative Strength Index compares the size of recent up-days with recent down-days on a 0–100 scale. Above 70 Bitcoin is considered overbought after a strong run; below 30 it is oversold after heavy selling.

Using RSI sensibly

In strong bull markets RSI can stay above 70 for weeks, and in bear markets below 30. Many traders look for divergences instead: price makes a new high but RSI makes a lower high, which suggests momentum is fading.