Williams %R: Range Position Oscillator Explained

Key Takeaways

• Williams %R runs from 0 (close at the top of the range) to -100 (close at the bottom), with overbought above -20 and oversold below -80.
• It is mathematically identical to the Fast Stochastic %K with a sign change; running both adds no new information.
• During strong uptrends, Williams %R can stay pinned near -20 or above for many sessions without a meaningful reversal.
• Divergence between price and %R, price makes a new high while %R makes a lower high, is a useful early warning of fading momentum.

What It Is

Williams %R, sometimes written Williams Percent Range, was developed by trader Larry Williams and first described in his 1973 book How I Made One Million Dollars Last Year Trading Commodities. The default lookback is 14 periods.

A reading near 0 means the close is at the top of the recent range, which is traditionally labeled overbought. A reading near -100 means the close is at the bottom of the range, labeled oversold. The common thresholds are -20 and -80.

The Intuition

Every range-based oscillator answers one question: where in the recent trading band is price right now? If you pick any N-bar window, the highest high and lowest low define the edges of that band. Price sits somewhere between them, and that position is a clean snapshot of short-term strength.

Williams %R gives you that position as a single number. Close near the top of the band and you know buyers have been winning the window. Close near the bottom and sellers have. The indicator does not predict what happens next. It just compresses the last 14 bars into a readable 0 to -100 line so you do not have to eyeball candles.

How It Works

The formula compares the current close to the highest high and lowest low over the lookback window:

%R = ((Highest High - Close) / (Highest High - Lowest Low)) * -100

Where:

Highest High = max high over the last N periods
Lowest Low   = min low over the last N periods
N            = lookback (default 14)

The multiplier of -100 is what gives the indicator its inverted scale. If you compute the same ratio without the negative sign, you get the Fast Stochastic %K on a 0 to 100 scale. Williams %R is mechanically the Fast Stochastic shifted and flipped.

Two zones get most of the attention:

• 0 to -20: overbought. Close is near the top of the range.
• -80 to -100: oversold. Close is near the bottom of the range.

Some platforms also watch for a move back across -50 as a rough trend-direction filter.

Worked Example

Take a stock with the following 14-day range:

• Highest High over 14 days: 110
• Lowest Low over 14 days: 100
• Today's Close: 108

Plug in:

%R = ((110 - 108) / (110 - 100)) * -100
   = (2 / 10) * -100
   = -20

A reading of -20 sits right at the overbought threshold. The close is near the top of its 14-day band, so momentum has been one-sided. If the stock is in a clear uptrend and above a long-term moving average, that reading is normal and is not a short signal. If the stock has been rangebound, a drift from -20 toward -50 could mark the end of the push.

Common Mistakes

1. Reading overbought as a sell signal. Williams %R can pin near -20 or above for long stretches during strong uptrends. Selling every time it pokes into the overbought zone in a trending market is a reliable way to fight the tape. Use a trend filter before acting on overbought readings.

2. Treating it as different from the Stochastic. Williams %R and the Fast Stochastic %K are the same calculation with a sign change and a shifted scale. If you are already running a Fast Stochastic you are not getting new information by adding Williams %R. Pick one.

3. Confusing it with RSI. RSI measures the ratio of up moves to down moves over the window. Williams %R measures where the close sits inside the high-low range. Both oscillate, both have overbought and oversold zones, but they respond to different things. RSI reacts to the size of gains and losses. Williams %R reacts to where price closes relative to its extremes. A stock can be overbought on one and neutral on the other.

4. Using the default without thinking about the timeframe. The 14-period default comes from the 1970s commodity context. On a 5-minute chart it behaves very differently than on a weekly chart. Shorten the lookback for faster reactions, lengthen it to filter noise.

5. Ignoring divergence. When price makes a new high but %R makes a lower high, the close is no longer reaching the top of its band as easily. That bearish divergence is a warning, not a trigger, but it is routinely skipped.

Frequently Asked Questions

Q: What is Williams %R in simple terms? Williams %R shows where today's closing price falls inside the highest high and lowest low of the past 14 bars, expressed as a number from 0 to -100. A reading near 0 means the close was near the top of the recent range; near -100 means near the bottom.

Q: How does Williams %R affect investment decisions? It identifies when price has pushed to an extreme within its recent range, prompting a reassessment of whether momentum is still intact. Readings near -20 in a sideways market suggest the rally may be stretched; in a clear uptrend they are normal and not a sell signal.

Q: What is a real-world example of Williams %R? A stock in a consolidation range produces three consecutive closes with Williams %R above -15, then %R drops sharply to -85 on one red day. That drop to oversold while the broader trend is still up is a potential entry signal for range-bound buyers.

Q: How can investors use Williams %R practically? Apply a trend filter: only buy oversold readings when the stock is above its 200-day moving average, and only sell overbought readings in downtrends. A simple rule: if you already run a Stochastic Oscillator, skip %R, they measure the same thing.

Q: How is Williams %R different from RSI? Williams %R measures where price closed inside the period's high-low range. RSI measures the ratio of up moves to down moves over the lookback. A stock can be overbought on Williams %R while still in neutral RSI territory, since the two indicators respond to different aspects of price behavior.

Sources

1. StockCharts ChartSchool. "Williams %R." https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/williams-r
2. Fidelity Learning Center. "Williams %R." https://www.fidelity.com/learning-center/trading-investing/technical-analysis/technical-indicator-guide/williams-r
3. TradingView. "Williams %R (%R)." https://www.tradingview.com/support/solutions/43000501985-williams-r-r/
4. LuxAlgo. "Williams %R Indicator: Oscillator for Overbought/Oversold Levels." https://www.luxalgo.com/blog/williams-r-indicator-oscillator-for-overbought-oversold-levels/

Disclaimer

This article is educational content only and is not financial advice. Nothing here is a recommendation to buy, sell, or hold any security. Consult a licensed advisor before making investment decisions.