Which indicator works best with MACD?

The indicator that works best with MACD is RSI, since the two measure different dynamics and confirm each other without redundancy.

Pairing MACD with RSI creates a strong momentum verification system; for example, a bullish MACD crossover combined with an RSI below 30 (oversold) provides a stronger buy signal.

Another strong pairing is MACD with the ADX (commonly set to 14), which doesn't indicate trend direction but quantifies trend strength; when ADX rises above 20 or 25, it confirms a significant trend is underway. The 200-day moving average works equally well for trend bias.