Traders Dynamic Index (TDI) Indicator for MT4
The Traders Dynamic Index (TDI) is a multi-component oscillator that plots a smoothed RSI, a fast and slow signal line, a market-base midline, and standard-deviation volatility bands in one window. It reads momentum, trend bias, and volatility together. It is free for MT4 and MT5, and updates on closed bars.
The Traders Dynamic Index, almost always shortened to TDI, packs four ideas that most traders watch separately into a single sub-window: where momentum sits (RSI), which way it is curling (fast and slow signal lines), whether the market is trending or ranging (the midline and band width), and how stretched price has become (volatility bands). Instead of stacking three or four indicators on one chart, you get a tidy momentum dashboard that the EarnForex build keeps faithful to Dean Malone's original design.
This page is an honest walkthrough, what each line actually measures, the inputs that change its behaviour, where it shines, and where it will frustrate you. The download is free, the source is Apache-2.0 license-clear, and the indicator runs on both MT4 and MT5.
What is the Traders Dynamic Index (TDI) indicator?
The Traders Dynamic Index (TDI) is a composite RSI oscillator that combines a smoothed Relative Strength Index, two moving-average signal lines drawn on that RSI, and Bollinger-style volatility bands around it, all inside one indicator window. Developed by Dean Malone and rebuilt by EarnForex for MetaTrader and cTrader, it is designed to show momentum, trend direction, and volatility expansion at the same time rather than forcing you to read several tools in sequence.
You will typically see five elements: the RSI value itself (often hidden or faint), a fast smoothing line of that RSI called the RSI Price Line or "green line", a slower Trade Signal Line or "red line", a market-base midline that sits at the centre of the volatility envelope, and an upper/lower band pair built from the standard deviation of the RSI. The horizontal levels at 32, 50, and 68 mark the oversold, equilibrium, and overbought zones.
How does the Traders Dynamic Index (TDI) indicator work?
TDI is built in layers, and understanding the order makes the signals obvious.
1. The RSI core. First it calculates a standard RSI over RSI_Period bars (default 13) using the chosen applied price. RSI measures the ratio of recent up-closes to down-closes, scaled 0-100. Everything else in TDI is derived from this single RSI series, the bands and both signal lines are smoothings or statistics of the RSI, not of price.
2. The two signal lines. A fast moving average of the RSI (the RSI Price Line, default a 2-period SMA) reacts quickly and acts like the green trigger line. A slower moving average (the Trade Signal Line, default a 7-period SMA) is the red line. When the fast green line crosses above the slow red line, momentum is turning up; a cross below signals momentum turning down, the same logic as an MACD crossover, but applied to RSI.
3. The volatility bands. Over the Volatility_Band lookback (default 34), TDI computes the standard deviation of the RSI and plots upper and lower bands at StdDev deviations (default ~1.618) from a simple moving average of the RSI. That moving-average centre is the market-base midline. Narrow bands mean the market is coiling and ranging; bands flaring wide mean a volatility expansion is underway. When the green line pushes outside a band, momentum is unusually stretched.
Reading it together. Bullish bias is the classic combination: green line above red, both above the 50 midline, and the midline itself rising. The 32/68 levels flag oversold/overbought. Because the EarnForex version can pull a higher-timeframe TDI onto a lower chart (UpperTimeframe), you can confirm an H1 entry against the H4 momentum picture without switching charts.
On repainting: TDI's lines are recalculated from the live RSI, so the current forming bar shifts tick by tick until that bar closes, like every oscillator. Once a bar closes, its values are fixed and do not repaint. The arrow/alert signals fire off a chosen bar via the TriggerCandle input: set it to the previous (closed) candle and signals are stable and do not redraw; set it to the current candle for faster but provisional alerts that can change before the bar closes.
Traders Dynamic Index (TDI) settings and parameters
These are the real inputs from the EarnForex build. The defaults reproduce Dean Malone's original TDI, so change them only with a reason, the standard deviation and band length in particular are tuned to behave the way most TDI guides describe.
| Parameter | Default | What it does |
|---|---|---|
| RSI_Period | 13 | Lookback for the underlying RSI. Lower (8-10) makes every line faster and noisier; higher (20-25) smooths the whole dashboard and cuts false crosses at the cost of lag. |
| RSI_Price | PRICE_CLOSE | Which price the RSI is calculated from. Close is the standard; switching to typical or median price slightly changes how the RSI reacts to bar shape. |
| Volatility_Band | 34 | Lookback for the standard-deviation bands. Shorter values make the bands hug the RSI and flare often; longer values give a steadier envelope that only widens on real volatility expansion. |
| StdDev | 1.6185 | How many standard deviations the bands sit from the midline. Higher pushes the bands wider so fewer band touches register; lower tightens them so the RSI breaches them more often. |
| RSI_Price_Line | 2 | Smoothing period for the fast green line. The default of 2 keeps it sensitive; raising it delays crossover signals but filters whipsaw in choppy conditions. |
| RSI_Price_Type | MODE_SMA | Averaging method for the green line (SMA, EMA, etc.). EMA reacts faster to the latest bars; SMA is the original, more even default. |
| Trade_Signal_Line | 7 | Smoothing period for the slow red signal line. Larger values make the red line steadier so crossovers are rarer and more reliable; smaller values speed up signals. |
| Trade_Signal_Type | MODE_SMA | Averaging method for the red signal line. Switch to EMA for quicker turns, or keep SMA to match the classic TDI behaviour. |
| UpperTimeframe | PERIOD_CURRENT | Optional higher timeframe to display on the current chart. Set to H4 while trading H1 to read higher-timeframe momentum without changing charts. |
| TriggerCandle | Previous | Which candle alerts evaluate. Previous uses the last closed bar for stable signals that do not redraw; Current fires on the live bar for faster but provisional alerts. |
Pros and cons (the honest version)
What it does well
- Four readings in one window, momentum, trend bias, signal-line crossover, and volatility, so you scan one sub-chart instead of stacking several indicators.
- Built on RSI, a battle-tested calculation, with sensible defaults that reproduce the original Dean Malone TDI out of the box.
- Closed-bar values do not repaint, and the TriggerCandle input lets you force alerts to evaluate only the last closed candle for stable signals.
- Multi-timeframe option displays higher-timeframe momentum on a lower chart, which helps align entries with the dominant trend.
- Free, open-source (Apache-2.0), and runs natively on both MT4 and MT5.
Where it falls short
- The current forming bar recalculates tick by tick like any oscillator, so green/red crosses on the live candle can appear and then vanish before the bar closes, wait for the close.
- It is RSI-derived and therefore lags price; in fast reversals the crossover confirms after a chunk of the move is already gone.
- In tight ranges the fast green and slow red lines cross repeatedly around the 50 line, producing whipsaw signals that lose money if traded blindly.
- Five lines plus bands and three levels is visually busy; new traders often misread which line is which until they hide the raw RSI.
- It is a momentum tool, not a complete system, it gives no stop, target, or position size, and works best filtered by structure, trend, or session context.
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How to install Traders Dynamic Index (TDI) on MetaTrader 4
- Download the free Traders Dynamic Index ZIP from this page and unzip it on your computer.
- In MetaTrader 4, open File then Open Data Folder, and navigate into MQL4 then Indicators (use MQL5/Indicators on MT5).
- Copy the Traders Dynamic Index .mq4 file (or .mq5 for MT5) into that Indicators folder.
- Switch back to MetaTrader and right-click the Navigator panel, then choose Refresh so the indicator appears.
- Expand Custom Indicators in the Navigator and drag Traders Dynamic Index onto the chart you want.
- In the inputs tab, set RSI_Period, the band settings, and the TriggerCandle option, then click OK.
- Confirm the TDI sub-window shows the green line, red signal line, midline, and volatility bands before you trade it.
Traders Dynamic Index (TDI) FAQ
Does the Traders Dynamic Index (TDI) repaint?
No on closed bars, once a candle closes, its TDI values are fixed and will not change. Like every oscillator, the current forming bar recalculates with each tick, so a crossover on the live candle is provisional until the bar closes. Set TriggerCandle to Previous to evaluate alerts only on the last closed bar for stable signals that do not redraw.
What is the best timeframe for TDI?
H1 and H4 tend to give the cleanest crossovers and the most meaningful band expansions. Lower timeframes like M5 and M15 produce far more whipsaw around the 50 midline; if you trade them, use the UpperTimeframe input to overlay higher-timeframe momentum as a filter.
How do I read TDI signals?
The core signal is the fast green line crossing the slow red line: a cross up with both lines above the 50 midline is a bullish bias, a cross down below 50 is bearish. The 32 and 68 levels flag oversold and overbought, and widening volatility bands mark a volatility expansion. Confirm crossovers on a closed bar before acting.
Is the Traders Dynamic Index free?
Yes. This is the open-source EarnForex build, released under the Apache-2.0 license, so you can download, use, and even modify it at no cost. There is no trial, unlock, or paid upgrade.
Does TDI work on MT5?
Yes. The download includes both the MT4 (.mq4) and MT5 (.mq5) versions, plus a cTrader build. Install the file that matches your platform into its Indicators folder and refresh the Navigator.
Can TDI be used as a standalone trading system?
It is best treated as a momentum and volatility filter rather than a full system. TDI tells you direction, momentum strength, and volatility, but it does not define stops, targets, or position size, and it whipsaws in ranges. Combine it with market structure, a trend filter, or session timing for the strongest results.