What is RSI?

The Relative Strength Index (RSI) measures the speed and size of recent price changes on a scale from 0 to 100. It is one of the most widely used momentum indicators.

Overbought and oversold

Readings above 70 are traditionally called overbought, and readings below 30 oversold. These are not automatic sell or buy points; they mark where momentum has stretched and may pause or reverse.

Trends bend the rules

In a strong trend, RSI can stay overbought or oversold for a long time. That is why RSI works best alongside context, not on its own.

Divergence

When price makes a new high but RSI does not, momentum is fading even as price rises. This divergence is a classic early warning that a move is losing strength.

Set an alert

You can set an RSI alert on any instrument to be notified when it crosses a level you choose, so you do not have to watch the chart. This is available on the free plan.