TDU Half Trend: a trailing trend line with an ATR channel
TDU Half Trend draws one line that tells you which way the market is leaning. The line trails below price in an uptrend and above price in a downtrend, and it only moves in the direction of the trend. When the trend flips, the line changes colour and an arrow marks the bar. An ATR channel around the line shows how much room price normally takes on either side.
What the indicator is
Half Trend is a trend-following overlay. It looks at a short window of recent bars, set by Amplitude (2 by default), and tracks four things in that window: the highest high, the lowest low, the average of the highs and the average of the lows.
In an uptrend the line sits at the highest of the recent lows it has seen and can only step up. Price pulling back does not drag it down. The trend flips to down when two things happen on the same bar: the average of the highs has dropped below the highest recent low of the run, and the bar closes below the low of the previous bar.
In a downtrend the logic is mirrored. The line sits at the lowest of the recent highs and can only step down. The trend flips to up when the average of the lows has risen above the lowest recent high of the run and the bar closes above the high of the previous bar.
On a flip the line starts from the level the previous trend ended on, which keeps it continuous on the chart.
Around the line the indicator draws a channel. Its half-width is the ATR Multiplier times half the ATR over ATR Period bars. With the defaults that is 2 times half of a 100-bar ATR, so the bands sit one full ATR above and below the line.
TDU Half Trend comes with SabrTrader on the Pro, Ultimate and Perpetual plans. There is no separate licence. The same plans include the rest of the premium library, such as TDU Wicked Wave, Market Structure and Volume Profile.
How to read it on the chart
| Element | Default look | What it tells you |
|---|---|---|
| HalfTrend line | Thick line, blue in an uptrend and red in a downtrend | The trend direction and the trailing level. It moves only with the trend. |
| ATR High | Red dots above the line | The line plus the channel half-width. |
| ATR Low | Blue dots below the line | The line minus the channel half-width. |
| Ribbons | Light red shading up to ATR High, light blue shading down to ATR Low | The area between the line and each band. |
| Up arrow | Blue triangle at the ATR Low band | The trend flipped from down to up on this bar. |
| Down arrow | Red triangle at the ATR High band | The trend flipped from up to down on this bar. |
Reading it takes one look. A blue line under price means the trend is up. A red line over price means it is down. A flat stretch of line means price is moving sideways or pulling back without having done enough to flip the trend. A rising staircase in blue, or a falling one in red, means the trend is still making progress.
The first 10 bars on the chart are used for warm-up and carry no line.
Three ways traders use it
Direction filter
Take long setups only while the line is blue and short setups only while it is red. The indicator then acts as a simple gate in front of whatever entry method you already use.
Trailing stop reference
Because the line never moves against the trend, it works as a trailing reference for an open position. The ATR band on the far side gives a wider alternative with room for normal noise.
Flip as a trigger
The arrow marks the bar where the trend changed. Some traders act on the flip itself, others wait for the first pullback toward the line after it.
Trend plus momentum
Combine the direction from Half Trend with a momentum read from TDU Wicked Wave, or with levels from TDU Pivots, so that direction, timing and location come from three separate tools.
See the trend at a glance
TDU Half Trend is included in Pro, Ultimate and Perpetual together with the whole premium library.
Download SabrTrader free See plans & pricingHow to add it in SabrTrader
- Open a chart of the instrument you trade.
- Add the indicator. Open the indicator list and search for Half Trend. It draws directly on the price panel.
- Keep the defaults for a first look. Amplitude 2, ATR Period 100 and ATR Multiplier 2.
- Adjust the sensitivity. Raise Amplitude if the trend flips more often than you want. A larger window makes the averages slower, so it takes a bigger move to flip.
- Decide what to show. The ATR High and ATR Low dot bands can be hidden separately in the plot settings. Hiding the HalfTrend plot hides the line together with its ribbons and arrows.
- Turn on the alert if you want a sound when the trend flips.
Settings reference
| Setting | Default | What it does |
|---|---|---|
| Amplitude | 2 | Number of bars in the window used for the highest high, lowest low and the two averages. Minimum 1. |
| ATR Period | 100 | Length of the ATR that sizes the channel. Minimum 1. |
| ATR Multiplier | 2 | Whole-number multiplier on half the ATR. Sets how far the two bands sit from the line. Minimum 1. |
| Trend up | Deep sky blue | Colour of the line and the up arrow in an uptrend. |
| Trend down | Red | Colour of the line and the down arrow in a downtrend. |
| Upper band | Red | Colour of the ribbon between the line and ATR High. |
| Lower band | Deep sky blue | Colour of the ribbon between the line and ATR Low. |
| Line width | 3 | Width of the HalfTrend line, from 0.5 to 20. |
| Enabled (Alerts) | Off | Raises an alert on a trend flip: "Half trend Up" or "Half trend Down". |
| Sound (Alerts) | Default sound | The WAV file played with the alert. |
The ribbons are always drawn at a light, fixed transparency so the candles stay readable through them.
Markets and data
TDU Half Trend needs only the high, low and close of each bar. It uses no volume, tick data or order flow, so it runs on futures, stocks, forex and crypto and on every bar type, including Renko, range, tick and volume bars. Any connected feed that delivers bars will do, for example Rithmic, dxFeed, Databento, IQFeed or Interactive Brokers.
The indicator calculates on bar close. Alerts fire on live bars only, so loading history does not replay old flips.
Five values are available in the data box and to strategies: ATR High, ATR Low, HalfTrend, Trend (1 in an uptrend, -1 in a downtrend) and Signal (1 on the bar of a flip to up, -1 on the bar of a flip to down, otherwise 0).
Frequently asked questions
What makes the trend flip?
Two conditions on the same bar. For a flip to down, the average of the highs over the Amplitude window must be below the highest recent low of the uptrend, and the bar must close below the previous bar's low. A flip to up is the mirror image with the average of the lows and a close above the previous bar's high.
Does the line repaint?
The indicator calculates once per closed bar, and each bar's value is stored when that bar closes. A flip arrow that has printed on a closed bar stays there.
What is the ATR channel for?
It gives scale. The bands sit a fixed number of ATRs from the line, so they widen in volatile conditions and narrow in quiet ones. Traders use the far band as a wider stop reference and the near band to judge how stretched price is from the trend line. The flip arrows are also drawn at the bands.
How do I get fewer flips?
Raise Amplitude. With the default of 2 the indicator reacts quickly. Larger values average more bars and need a more decisive move before the trend changes. ATR Period and ATR Multiplier change the channel only and have no effect on when the trend flips.
Does it work on Renko charts?
Yes. The calculation only reads bar highs, lows and closes, so it treats Renko bricks like any other bar. The screenshot on this page is taken on a median Renko chart.
Is TDU Half Trend a separate purchase?
No. It is included in the Pro, Ultimate and Perpetual plans. See pricing or the full list of premium indicators.
One line for the trend
TDU Half Trend ships with SabrTrader on Pro, Ultimate and Perpetual. No add-on fee and no separate licence.
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