The Mass Index identifies potential trend reversals by measuring the narrowing and widening of the range between high and low prices, generating a "reversal bulge" signal when the range first expands then contracts. It is a unique contrarian tool for stock and forex traders. Combine Mass Index reversal signals with momentum tools from our indicator guide library for higher-probability entries.
Mass Index = Sum of [EMA(9) of (High − Low) / EMA(EMA(9)) of (High − Low)] over 25 periods. When the Mass Index rises above 27 and then falls back below 26.5, it produces a reversal bulge signal. The direction of the reversal depends on the preceding trend and is confirmed by an EMA crossover.
Keltner Channels plot an EMA with upper and lower bands based on <a href="/academy/indicators/atr" class="text-primary hover:underline">ATR</a>, producing smoother envelopes than <a href="/academy/indicators/bollinger-bands" class="text-primary hover:underline">Bollinger Bands</a> — and the two are frequently used together for the TTM Squeeze setup. This combination identifies low-volatility compression zones that precede explosive <a href="/guides/trade-breakouts" class="text-primary hover:underline">breakout</a> moves in any market. Apply Keltner Channels on <a href="/tools/platforms/tradingview" class="text-primary hover:underline">TradingView</a> and overlay Bollinger Bands to spot squeeze conditions with a single glance.
Donchian Channels plot the highest high and lowest low over a specified period, forming a simple but effective volatility envelope and breakout system that powered the legendary Turtle Trading strategy. They are widely used in <a href="/market/forex" class="text-primary hover:underline">forex</a> and <a href="/market/crypto" class="text-primary hover:underline">crypto</a> for trend-following breakout <a href="/strategies" class="text-primary hover:underline">strategies</a>. Compare Donchian Channels with <a href="/academy/indicators/bollinger-bands" class="text-primary hover:underline">Bollinger Bands</a> and <a href="/academy/indicators/keltner-channels" class="text-primary hover:underline">Keltner Channels</a> in our <a href="/academy/indicators" class="text-primary hover:underline">indicator guide library</a>.
Historical Volatility measures the annualised standard deviation of past log price returns, giving traders a statistical benchmark for how volatile an asset has been. It is essential for options pricing and risk management in <a href="/market/stocks" class="text-primary hover:underline">stocks</a> and increasingly in <a href="/market/crypto" class="text-primary hover:underline">crypto</a> derivatives. Use our <a href="/tools/calculators/position-size-calculator" class="text-primary hover:underline">position size calculator</a> to incorporate HV into your risk management workflow.
The Ulcer Index measures downside volatility by calculating the depth and duration of drawdowns from recent highs, providing a risk metric that focuses exclusively on the pain investors care about most. It was created by Peter Martin specifically for evaluating <a href="/market/stocks" class="text-primary hover:underline">stock</a> fund performance. Incorporate the Ulcer Index into your risk management alongside tools from our <a href="/academy/indicators" class="text-primary hover:underline">indicator guide library</a> to protect capital during volatile markets.