TRIX: The Triple Smoothed Momentum Oscillator

Key Takeaways

• TRIX is the one-period percentage rate of change of an EMA of an EMA of an EMA of the close.
• Hutson designed it to suppress price noise shorter than the chosen smoothing length.
• Reading TRIX without its signal line is the most common error and ignores the published primary signal.
• Compared with MACD, TRIX prints smoother turns but tends to lag by a bar or two.

What It Is

TRIX is an oscillator that fluctuates around zero. It is plotted below price, usually with a signal line drawn as a 9-period EMA of TRIX itself.

The name comes from triple exponential. The indicator takes a closing price series, runs it through three sequential EMAs of the same length, and then computes the one-period percentage change of that triple-smoothed line. The triple smoothing removes short oscillations, so what remains is the underlying directional drift.

The Intuition

A single EMA already smooths price. Two EMAs in sequence smooth it further, and three in sequence remove almost all high-frequency wiggle. The cost is lag; the benefit is that any move TRIX captures is a genuine shift in the longer drift, not a one-bar spike.

By converting the triple-smoothed value into a percent rate of change, Hutson made TRIX directly comparable across stocks at different prices. A 0.2 percent TRIX reading means the same thing on a 10 dollar stock and on a 1,000 dollar stock.

How It Works

The TRIX(15,9) standard uses a 15-period smoothing length and a 9-period signal line:

EMA1 = EMA(close, 15)
EMA2 = EMA(EMA1, 15)
EMA3 = EMA(EMA2, 15)
TRIX = 100 x (EMA3 - EMA3_prior) / EMA3_prior
Signal = EMA(TRIX, 9)

Each EMA pass uses the same 15-period smoothing. The percent change of the final EMA is multiplied by 100 to express it in percent. The signal line is then a 9-period EMA of TRIX.

The three published signals are signal line crossovers, centerline crossovers, and divergences. A TRIX cross above its signal line is bullish; a cross below is bearish. A TRIX cross above zero signals the underlying triple-smoothed line is now rising. A divergence between price and TRIX warns that the latest price move lacks underlying momentum.

Worked Example

A stock closes at 50 on day one. After running through three 15-period EMAs, EMA3 prints 47.50. The next day, the close is 51, the EMAs update, and EMA3 prints 47.65. The new TRIX reading is:

TRIX = 100 x (47.65 - 47.50) / 47.50 = 0.316%

Over the next week, TRIX climbs from 0.10 to 0.40, then 0.55, then 0.50, then 0.42. The 9-period EMA signal line lags behind at 0.30, 0.35, 0.40, 0.45, 0.47. On the day TRIX prints 0.42 and the signal sits at 0.47, TRIX has crossed below its signal line. That is the textbook sell signal, even though price may still be drifting up.

Common Mistakes

1. Comparing TRIX numbers across timeframes. A weekly TRIX of 0.5 and a daily TRIX of 0.5 reflect very different rates. The percent change is per bar, not per day.
2. Reading TRIX as overbought or oversold. TRIX has no fixed bounds. The values that count as extreme on one stock are unremarkable on another with higher volatility.
3. Ignoring the signal line. Most TRIX trading rules from Hutson and later writers center on the TRIX vs signal line cross. Reading the raw line alone removes the published timing component.
4. Using too short a smoothing length. A 5-period TRIX reintroduces noise the triple smoothing was supposed to remove. The standard 14 or 15 is there for a reason.
5. Treating TRIX as a leading indicator. Triple smoothing adds lag. TRIX confirms turns more cleanly than MACD but it does not anticipate them earlier than MACD does.

Frequently Asked Questions

What is the TRIX oscillator in simple terms? The TRIX oscillator measures how fast a triple-smoothed average of the closing price is changing in percent. It filters out short-term wiggles so only the underlying drift remains.

How does the TRIX oscillator affect investment decisions? Swing traders use TRIX signal line crossovers to time entries inside a confirmed trend. A bullish cross above zero supports adding to long positions; a bearish cross below zero supports trimming.

What is a real-world example of the TRIX oscillator? On a steadily rising broad index like the S and P 500, TRIX usually holds above zero for long stretches and crosses below its signal line only at meaningful pullbacks. That behavior is how Hutson originally documented it.

How can investors use the TRIX oscillator effectively? Pair TRIX with its signal line and with a higher-timeframe trend filter. Use signal line crosses in the direction of the larger trend and require a centerline cross before reversing a position.

How is the TRIX oscillator different from MACD? MACD subtracts two EMAs of price. TRIX takes the percent change of a single EMA that has itself been smoothed three times. TRIX is smoother and lags slightly more than MACD.

Sources

1. StockCharts ChartSchool. TRIX. https://chartschool.stockcharts.com/table-of-contents/technical-indicators-and-overlays/technical-indicators/trix
2. Trading Technologies. TRIX. https://library.tradingtechnologies.com/trade/chrt-ti-trix.html
3. TradingView Help. TRIX. https://www.tradingview.com/support/solutions/43000502331-trix/
4. MultiCharts. TRIX Indicator Explained. https://www.multicharts.com/trading-software/index.php?title=TRIX

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.