What Is the RSI Heatmap?

The Relative Strength Index measures how one sided recent price action has been on a scale of 0 to 100. It weighs the size of recent gains against the size of recent losses over a fixed lookback, so a coin that has closed higher on most of the recent candles scores high, and one that has closed lower on most of them scores low.

A heatmap applies that single reading to the whole market at once. Rather than opening a hundred charts, you get one view of where momentum is stretched, where it is fading, and how much of the market sits in each condition. The scatter above plots every coin in the top 100 by market capitalisation against its RSI, and the band above it counts how many coins fall into each zone.

RSI was introduced by J. Welles Wilder in New Concepts in Technical Trading Systems in 1978 and remains one of the most widely used momentum oscillators in any market, not just crypto.

How to Read the Heatmap

Coins are plotted left to right by market cap rank, so Bitcoin and Ethereum sit at the left edge and the smaller names spread out to the right. Vertical position is the RSI reading, and the tinted bands mark the conventional thresholds: above 70 is overbought, below 30 is oversold.

Two shapes are worth watching. When the cloud of dots sits high across the full width, momentum is broad and the market is running hot as a whole. When it clusters low, selling has been indiscriminate rather than name specific. A split, where the large caps sit high while the long tail sits low, usually means capital is concentrating at the top of the market instead of rotating down it, which is the same behaviour the Altcoin Season Index tracks over a longer window.

How We Calculate RSI

Each coin is scored with Wilder's RSI(14) on hourly closes. The first fourteen price changes seed an average gain and an average loss, then every later change is folded in with Wilder's smoothing rather than a simple moving average. The two averages give a relative strength ratio, which is mapped onto the 0 to 100 scale.

Everything on this page is computed in your browser from a single request for the top 100 coins, and it recalculates on every visit. The composite figure in the band is an equal weighted average across those 100 coins, so a small cap moves it exactly as much as Bitcoin does. That is deliberate: it is a breadth reading, not a cap weighted one.

Choosing a Timeframe

The toggle above switches every figure on the page between the 1 hour, 4 hour, 12 hour and daily readings. Shorter timeframes react faster and swing wider, so they answer questions about whether a move has run too far in the last session. Longer ones smooth that noise out and sit closer to the midline, which makes them better for judging the condition of a trend rather than the state of a single move.

The same coin can read overbought on the 1 hour and neutral on the daily without any contradiction: they are measuring different windows. Traders generally read the longer timeframe first to establish direction, then use the shorter one for timing. For a full price history on any single asset, open its page from the table above, such as Bitcoin or Ethereum.

What RSI Does Not Tell You

RSI describes what price has already done. It is not a forecast, and neither threshold is a signal on its own. The most common mistake is treating overbought as a reason to sell: in a strong trend RSI can sit above 70 for days while price keeps climbing, and the same holds in reverse during a sustained decline.

It is also blind to context. A coin can read oversold because of a protocol failure, a delisting, or an unlock, none of which a momentum oscillator can see. Traders often pair RSI with divergence analysis, volume, and a longer timeframe reading before drawing any conclusion, and treat a single number as a prompt to look closer rather than an answer.