Williams %R Indicator Explained

Williams %R (Williams Percent Range) is a momentum oscillator that, like the Stochastic, measures where the close sits within the recent high-low range — but on an inverted −100 to 0 scale.

The Scale

• 0 to −20: overbought (close near the top of the range).
• −80 to −100: oversold (close near the bottom of the range).
• Around −50: mid-range.

It is essentially the Stochastic %K flipped, so it reads the same momentum information from a slightly different angle.

How to Use It

Reversals. Williams %R turning up from below −80 can signal a bounce; turning down from above −20 can signal a pullback.

Momentum confirmation. Staying in the upper zone confirms strength; staying in the lower zone confirms weakness. In strong trends it can sit pinned at an extreme — do not fade it blindly.

The reliable play is to use it for timing within a trend you have already confirmed with a trend filter, rather than as a standalone reversal signal.

Building It in Setup.Cash

Add the Williams %R indicator in the builder with its lookback period (default 14), and condition on the level (e.g., crossing up through −80). Or describe it to text-to-strategy.

Tuning

• Length 14: standard.
• Shorter (7–10): faster, noisier.
• Longer (21+): smoother, slower.

Williams %R vs Stochastic

They carry nearly identical information. Choose whichever scale you find easier to read; many traders prefer Williams %R for its single-line simplicity versus the Stochastic's two lines.

Build a Custom Version

In the Indicators Lab you can build it with highest and lowest, or generate a custom momentum oscillator with AI.

Williams %R is a clean, single-line momentum gauge. Use it for timing inside a confirmed trend, and always backtest before going live.