Direct Answer
TRIX is a momentum oscillator built from a triple-smoothed exponential moving average of closing price: an EMA of price is smoothed by a second EMA, which is smoothed by a third EMA, and TRIX plots the percentage rate of change of that final line from one day to the next. A TRIX reading crossing above zero is commonly read as bullish momentum; crossing below zero, bearish. Because it runs three EMAs in sequence, TRIX filters out more short-term price noise than a single-smoothed indicator like MACD, at the cost of confirming momentum shifts even later.
Key Takeaways
- TRIX = the percentage rate of change, day over day, of a triple-smoothed exponential moving average of closing price (EMA of an EMA of an EMA).
- A 15-period EMA is commonly cited as the default for each of the three smoothing steps, though the period is a convention that varies by platform and timeframe.
- A TRIX crossing above zero is commonly read as bullish momentum; below zero, bearish, but three layers of smoothing make this a slower, later confirmation than a single-EMA indicator.
- Triple smoothing is the whole point: it's designed to filter out short-term price and volume "insignificant" fluctuations that other momentum oscillators can react to.
- Some platforms optionally add a signal line to TRIX (commonly a short EMA of the TRIX line itself), though this isn't part of TRIX's core definition and specific period conventions vary by platform.
What Is TRIX?
TRIX (triple exponential average) is a momentum oscillator that measures the rate of change of a price series that has already been smoothed three separate times by an exponential moving average. Rather than comparing two EMAs of different lengths the way MACD does, TRIX runs a single EMA period through three successive smoothing passes, then expresses how much that final, heavily filtered line moved from the prior day, as a percentage.
The triple smoothing is the defining feature. Each additional EMA pass removes more of the short-term noise that's left over in the line beneath it, so by the time TRIX measures the rate of change of EMA3, most single-day and short-swing price fluctuations have already been filtered out. The tradeoff is time: three layers of lag stacked on top of each other mean TRIX confirms a momentum shift well after it begins, in exchange for a smoother, less choppy line.
The Formula
Step 1: EMA1 = n-period EMA of closing price (commonly n = 15).
Step 2: EMA2 = n-period EMA of EMA1.
Step 3: EMA3 = n-period EMA of EMA2.
TRIX = ((EMA3 today − EMA3 yesterday) ÷ EMA3 yesterday) × 100.
TRIX is built directly on top of the exponential moving average, just run three times in a row instead of once: EMA1 smooths raw closing price, EMA2 smooths EMA1, and EMA3 smooths EMA2. The final step doesn't compare EMA3 to another moving average the way MACD compares two EMAs, it compares EMA3 to itself from the previous period, expressed as a percentage rate of change rather than a raw price-unit difference.
Worked Example
Hypothetical example, for education only.
Suppose a stock's 15-period EMA of closing price (EMA1) has been smoothed twice more, and the resulting EMA3 stood at 81.20 yesterday and 81.55 today.
TRIX = ((81.55 − 81.20) ÷ 81.20) × 100 = (0.35 ÷ 81.20) × 100 = 0.43
A TRIX reading of 0.43 is positive and above zero, which is commonly read as bullish momentum in the triple-smoothed trend line. If EMA3 had instead fallen from 81.20 to 80.90, TRIX would come out to roughly −0.37, commonly read as bearish. Because EMA3 has already absorbed three rounds of smoothing, a given day's TRIX value reflects a trend shift that began well before that day, it's a confirmation of an already-developing move, not an early warning of one.
Common TRIX Signals
Zero-line crossover
TRIX crossing above zero is commonly read as bullish momentum in the underlying triple-smoothed trend; crossing below zero, bearish. This is the indicator's primary signal. Because TRIX only turns positive once the triple-smoothed EMA3 line itself is rising day over day, the crossover tends to trail the actual start of a price move by a wider margin than a single-EMA-based indicator would.
Signal-line crossover
Some platforms optionally add a signal line to TRIX (commonly a short EMA of the TRIX line itself), similar in concept to MACD's signal line, though this isn't part of TRIX's core definition and specific period conventions vary by platform. Where offered, a TRIX cross above that signal line is read the same directional way as the zero-line cross, and some traders treat it as an earlier, if noisier, cue.
Divergence
As with other momentum oscillators, a divergence between price and TRIX, price making a higher high while TRIX makes a lower high, or the reverse, is commonly read as a sign that underlying momentum is weakening even though price is still extending. Divergence flags disagreement between price and the indicator; it is not, on its own, a confirmed reversal signal.
Standard and Alternative Settings
| EMA period (n) | Responsiveness | Common use |
|---|---|---|
| 15 | Balanced (commonly cited default) | General-purpose swing/trend analysis |
A 15-period EMA at each of the three smoothing steps is commonly cited as the default, but this is a convention, not a fixed rule, verify the default your specific charting platform ships with, since it can vary. A shorter period reacts faster to price at the cost of more zero-line crossovers in a choppy market; a longer period smooths further but confirms momentum shifts even later.
Why TRIX Produces False Signals
- Sideways markets, TRIX can oscillate back and forth across zero with no sustained follow-through when price isn't trending, just like other EMA-based oscillators.
- Triple-smoothing lag, because EMA3 is itself an EMA of an EMA of an EMA, a genuine trend shift can be well underway, or even close to reversing again, before TRIX confirms it.
- Divergence without price confirmation, a TRIX divergence can appear well before, or fail to precede, an actual price reversal.
- Ignoring the broader trend, a bullish zero-line crossover against a strong prevailing downtrend has, on average, less follow-through than one aligned with the dominant trend.
- Treating TRIX's raw value as comparable across assets, because TRIX is expressed as a percentage rate of change rather than a price-unit value, its scale differs from MACD's, and its magnitude also varies with each asset's typical volatility.
Common Mistakes
- Treating every zero-line crossover as an immediate trade trigger, most traders pair it with trend or price-structure context first, given how late the signal typically arrives.
- Expecting TRIX to behave like MACD, the extra smoothing pass and the percentage-based output mean the two aren't directly interchangeable, even though both are EMA-derived momentum tools.
- Using TRIX alone to time entries on a strongly ranging asset, it's a trend/momentum tool and behaves choppiest exactly where there's no sustained trend to measure.
- Applying a default 15-period setting across every timeframe without checking whether it still fits, a 15-period TRIX on a 1-minute chart behaves very differently than on a daily or weekly chart.
Limitations
TRIX is a lagging indicator, and more so than most: every input is an EMA of past closing prices, and three of those EMAs are stacked in sequence, so it confirms a momentum shift well after that shift began rather than predicting it in advance. It carries no information about volume, liquidity, order-book depth, or fundamentals, and, like other technical indicators. It is a mathematical interpretation of historical price data, not a guarantee of future performance.
Three Rounds of Smoothing and What They Remove
TRIX applies exponential smoothing three times before measuring the rate of change, which strips out short-term fluctuation thoroughly. The output is a clean line with few false crossings, and the cost of that cleanliness is delay proportional to the smoothing applied.
That makes it suited to longer-horizon work and poorly suited to anything requiring timely entries. On a weekly or daily chart used to establish trend direction, the lack of noise is genuinely useful. On an intraday chart used for entries, the delay means acting well after the move began.
The mistake is reading zero-line crossings as entry signals. The crossing indicates the smoothed momentum changed sign, which occurs some distance into a move, and a system built on those crossings will consistently enter late and exit late. As a trend confirmation rather than a trigger it behaves better.
Triple smoothing also cannot distinguish a genuine turn from a large single move. A sharp reversal appears in the output gradually, arriving over several periods, which means the indicator understates the abruptness of exactly the events that matter most.
TRIX FAQs
What does TRIX stand for?
TRIX is short for triple exponential average. It's a momentum oscillator built by taking an exponential moving average of price, smoothing that average a second time, smoothing it a third time, and then measuring the percentage rate of change of that final, triple-smoothed line.
What does a TRIX crossing above zero mean?
A TRIX crossing above zero is commonly read as bullish momentum, since it means the triple-smoothed EMA is now rising day over day. A cross below zero is commonly read as bearish momentum. Because TRIX is built from three layers of EMA smoothing, this crossover confirms a shift that has typically already been underway for a while.
What is the standard TRIX period?
A 15-period EMA is commonly cited as the default for each of the three smoothing steps, though this is a convention rather than a fixed rule, and platforms vary in what they ship as the default.
How is TRIX different from MACD?
MACD subtracts one EMA from another to produce a raw price-unit value. TRIX applies three successive rounds of EMA smoothing to a single series and then expresses the day-over-day change as a percentage rate of change, which filters out more short-term noise but reacts to new momentum shifts more slowly.
Is TRIX a leading or lagging indicator?
Lagging. Every input is an EMA of past closing prices, and TRIX applies three of them in sequence, so it confirms a momentum shift well after that shift began rather than predicting it in advance.
Can TRIX be used with a signal line?
Some platforms optionally add a signal line to TRIX, commonly a short EMA of the TRIX line itself, though this isn't part of TRIX's core definition and specific period conventions vary by platform. Where offered, a TRIX crossing above or below that signal line is read the same way a MACD signal-line crossover is, as an added confirmation layer rather than a replacement for the zero-line read.
Why is the smoothing applied three times rather than once?
Each pass removes more short-period variation, and applying it three times filters out cycles shorter than the chosen period far more thoroughly than a single pass. The intent is an oscillator that responds only to movements longer than the setting. The cost is substantial lag, since three sequential smoothings each delay the response.
What does the rate-of-change step add after the smoothing?
Taking the percentage change of the triple-smoothed series converts a smoothed price line into an oscillator centred on zero, so the reading measures the direction and pace of the smoothed trend rather than its level. This is what allows a zero-line crossing to be read as a trend change. Without the final step the output would be another moving average rather than an oscillator.
Is the indicator suitable for short-term trading?
The triple smoothing makes it structurally slow, so signals arrive well after a move begins. Shortening the period to compensate reintroduces the noise the smoothing was designed to remove, which undermines the construction's purpose. It is better suited to identifying sustained trends than to timing short-term entries.