Ultimate Oscillator Explained

Most oscillators have one weakness: they're locked to a single lookback, so they scream "oversold" on one horizon while another horizon says the selling has barely started. Larry Williams' Ultimate Oscillator fixes this by blending buying pressure across three timeframes at once (defaults 7, 14, and 28), weighted 4 : 2 : 1.

How It Works

For each period, the oscillator measures buying pressure (close minus true low) relative to true range, then combines the three readings into a single 0–100 line:

• Above 70: overbought across the blended horizons.
• Below 30: oversold — and because three timeframes agree, it's a more meaningful oversold than a single-period RSI.
• 50: the bull/bear midline.

The Classic Divergence Strategy

Williams designed a specific three-step signal:

1. Bullish divergence: price makes a lower low, but the oscillator makes a higher low.
2. The oscillator dipped below 30 at the first low (a real oversold reading).
3. Entry: when the oscillator breaks above its divergence high.

The mirror image gives the short setup. The multi-timeframe blend makes these divergences noticeably more reliable than single-period ones.

Building It in Setup.Cash

Add the Ultimate Oscillator in the strategy builder with its short/medium/long periods, and condition on levels or crossings just like RSI. A simpler automated pattern: buy the cross back above 30, filtered by a rising long-term moving average.

Tuning

• 7/14/28: the canonical setting — rarely worth changing.
• Scale all three together (e.g. 5/10/20) to make the whole indicator faster; keep the 1:2:4 ratio.
• Thresholds 65/35 trade more often; 75/25 only extremes.

Related Reading

If you like multi-horizon momentum, see also the TSI (True Strength Index) and the KST (Know Sure Thing) in the extended library. Backtest divergence rules carefully — they trigger rarely, so you need long test windows.