ADX Trend Strength

ADX measures the strength of directional movement, not the direction itself. This is by design - it answers 'how strong is the trend?' not 'which way?' The +DI and -DI lines provide the direction. This separation allows ADX to identify strong trends regardless of whether they're up or down.

ADX measures trend strength (directional movement). ATR measures volatility (average range size). ATR can be high in ranging markets (big swings both ways); ADX would be low. Use ATR for stop sizing and volatility assessment; use ADX for trend confirmation.

Theoretically ADX is bounded 0-100, but in practice it rarely exceeds 60-70. Readings above 50 are extreme and often indicate trend exhaustion. Most tradeable trends see ADX between 25-45.

ADX is best as a filter, not a standalone system. Use ADX to confirm whether the market is trending before applying other indicators like EMA crossovers, MACD, or breakouts. ADX tells you IF to trade trend strategies, not exactly when to enter.

+DI measures upward directional movement (current high minus previous high, when positive). -DI measures downward directional movement (previous low minus current low, when positive). Both are smoothed over the ADX period (default 14).

Use ADX as a filter for MA signals. Only take MA crossover trades when ADX > 25. This dramatically reduces whipsaws because you're only trading in trending conditions. Example: 9/21 EMA cross + ADX > 25 = confirmed signal.

This suggests the trend exists but directional conviction is weakening. ADX will likely start falling soon. It's an early warning to tighten stops and prepare for potential trend change or reversal.

ADX above 25 occurs roughly 40-60% of the time on liquid instruments. DI crossovers while ADX > 25 might occur 4-8 times per year per instrument. ADX is more of a filter than a signal generator.

ADX 20-25 is the 'developing' zone. Trends may be starting but aren't confirmed. You can trade with reduced size, or wait for ADX > 25. Many traders wait for 25+ to avoid false starts.

High ADX (> 25) favors directional strategies (long calls/puts, spreads in trend direction). Low ADX (< 20) favors neutral premium selling (iron condors, strangles). ADX guides which options regime to operate in.

Compare swing highs/lows of price to swing highs/lows of ADX. Bearish divergence: price higher high, ADX lower high. Bullish divergence: price lower low, ADX higher low. These warn of trend weakening before it's obvious in price.

Lower timeframes may need shorter periods (10-12) for responsiveness. Higher timeframes work with standard (14) or longer (18-20) for smoothness. Test on out-of-sample data for your specific instruments.

Daily: Categorize universe by ADX regime (trending > 25, developing 20-25, ranging < 20). Apply trend strategies to trending bucket, premium selling to ranging bucket, watch developing for breakouts. Rebalance as regimes shift.

Sustained ADX above 40 (15+ bars) indicates exceptional trend strength but also increases exhaustion probability. Trends can't accelerate forever. Begin taking profits and tightening stops even if no reversal signal yet.

Wide DI gap (15+ points) = strong conviction, hold/add. Narrowing gap = weakening conviction, reduce/tighten. DI convergence toward cross = prepare to exit. DI expansion after cross = add to position.