The True Strength Index was developed by William Blau in 1991 to solve a specific problem with raw momentum oscillators: they’re noisy. RSI, Stochastic, and similar tools generate plenty of false signals because their underlying math reacts to every short-term price wiggle. Blau’s solution was to take raw momentum and smooth it twice — once with a long EMA, once with a short EMA — producing a single line that captures real momentum changes without the noise.
The result is the cleanest-reading momentum oscillator I use on MT4. TSI doesn’t catch every move (it lags slightly), but the moves it does catch are real. For swing trading on H4 and Daily, TSI is one of my preferred tools.
What is the True Strength Index?
TSI is calculated by taking raw price changes (close-to-close differences), smoothing them with a 25-period EMA, then smoothing that result with a 13-period EMA. The double smoothing is what makes TSI different from every other momentum oscillator — it dampens the noise that single-pass calculations carry.
The output is a centred oscillator that swings around zero, typically ranging from -50 to +50 on most forex pairs. Above zero = bullish momentum; below zero = bearish. A 7-period EMA of the TSI itself serves as the signal line for crossover entries — same idea as MACD’s signal line.
How TSI Works on MT4
TSI isn’t in MT4’s default oscillator list. You’ll need to install our custom version – see install custom indicators on MT4.
Once installed, TSI plots in a sub-window with the TSI line plus an optional signal line.
Three signal types matter:
The signal-line cross. TSI crossing above its signal line = bullish entry trigger. Crossing below = bearish. Same concept as MACD’s signal line, but TSI’s double-smoothed math means fewer false crossovers.
The zero-line cross. TSI crossing above zero = trend has flipped bullish. Below zero = bearish. Slow but reliable trend filter.
Divergence. Same as other oscillators — price higher highs while TSI prints lower highs is bearish divergence. TSI’s smoothness makes divergences cleaner to spot than RSI’s.
Key Features
- Double-smoothed math eliminates noise from raw momentum
- Centred on zero, similar to MACD but smoother
- Optional signal line for crossover entries
- Non-repainting once candles close
- Configurable smoothing parameters (default 25/13/7)
- Effective for divergence detection on swing timeframes
Best Settings for TSI Indicator
Blau’s original settings (25/13/7) are what most traders use. Adjustments are rarely worth it.
| Parameter | Default (Blau) | Faster Variant | Slower Variant |
|---|---|---|---|
| Long EMA | 25 | 13 | 40 |
| Short EMA | 13 | 7 | 20 |
| Signal Line | 7 | 5 | 10 |
Recommended starting point: Default 25/13/7 on H4 or Daily. TSI is too slow for M5 scalping; too fast for monthly position trading.
Pros and Cons
| Pros | Cons |
|---|---|
| Cleanest momentum reading on MT4 – very few false crossovers | Lags compared to RSI – misses early entries |
| Effective for divergence on swing timeframes | Not built into MT4 by default – requires manual install |
| Centred on zero with optional signal line – flexible signals | Less popular than RSI/MACD – fewer trading literature references |
| Non-repainting, suitable for backtesting | Best on H4 and Daily; weak below H1 |
How to Install TSI on MT4
Step 1: Download TSI.ex4 (link below).
Step 2: Drop into MQL4/Indicators via File > Open Data Folder.
Step 3: Refresh Navigator (Ctrl+N), drag TSI onto your chart.
Step 4: Set Long EMA 25, Short EMA 13, Signal Line 7. Add zero level. Click OK.
Trading Strategy: TSI Signal-Line Cross with Trend Filter
Setup: TSI(25/13/7) with zero level. 50 EMA on price for trend context.
Buy Signal:
1. Price is above the 50 EMA (uptrend)
2. TSI is above zero (bullish momentum)
3. TSI line crosses above its signal line
4. Enter long on the close of the cross candle
Sell Signal:
1. Price is below the 50 EMA (downtrend)
2. TSI is below zero
3. TSI line crosses below its signal line
4. Enter short on the close
Stop Loss: Beyond the recent swing extreme (50-100 pips on H4).
Take Profit: 1:2 R:R or trail by the 50 EMA.
The double zero-line + signal-line filter is what makes TSI signals reliable. Without both confirmations, TSI alone can produce premature entries at trend exhaustion points.
TSI vs MACD
| Feature | TSI | MACD |
|---|---|---|
| Calculation | Double-smoothed price changes | Difference of two EMAs |
| Smoothness | Very smooth (double EMA) | Moderately smooth |
| Signal speed | Slower | Faster |
| False crossovers | Few | More |
| Histogram | No | Yes |
Verdict: TSI for cleaner, slower signals on swing timeframes. MACD when you want a faster signal-line trigger plus the histogram for momentum acceleration. They overlap conceptually but produce different signal cadences.
Frequently Asked Questions
Is the TSI indicator free?
Yes. Custom version available below.
Does TSI repaint?
No. Locks in once the candle closes.
Best TSI settings for forex?
Default 25/13/7 on H4 and Daily. TSI is too slow for short-timeframe scalping.
TSI vs MACD – which to use?
TSI for swing trading where signal cleanliness matters more than speed. MACD for day trading where you want faster crossovers and the histogram. They complement rather than replace each other.
Can I use TSI on MT5?
Yes. Custom TSI works identically on both platforms.
Download TSI Indicator for MT4 – Free
- Multi-timeframe display – H4 and D1 TSI on your H1 chart
- Signal-line cross alerts – popup, email, push notifications
- Zero-line cross alerts – notification when TSI flips sign
- Divergence detection – automatic divergence drawing
Platform: MT4 (Build 1000+)
File type: .ex4
File size: 16 KB
Version: 2.1
Last updated: April 2026
Download the TSI Indicator – Free Instant Access
No payment. No catch. Enter your email below and the TSI Indicator file lands in your inbox within 60 seconds. Here’s everything you get:
- The non-repainting TSI Indicator file (.ex4) – install in 30 seconds
- Step-by-step installation guide with chart screenshots
- Best-performing settings for day trading and swing trading
- The exact signal-line cross rules I use in live trading
- Weekly trading insights from a developer with 16+ years of market experience
Download the TSI (True Strength Index) Indicator – Free Instant Access
No payment. No catch. Enter your email below and the TSI (True Strength Index) Indicator file lands in your inbox within 60 seconds. Here’s everything you get:
- The non-repainting TSI (True Strength Index) Indicator file (.ex4) – install in 30 seconds
- Step-by-step installation guide with chart screenshots
- Best-performing settings for scalping, day trading, and swing trading
- The exact entry and exit rules Dom uses in live trading
- Weekly trading insights from a developer with 16+ years of market experience
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Overall Rating: 4.4/5
| Category | Rating |
|---|---|
| Accuracy | 4.5/5 |
| Ease of Use | 4.2/5 |
| Features | 4.3/5 |
| Value | 4.6/5 |
Related Indicators
- MACD Indicator MT4 – The other dominant signal-line momentum oscillator
- RSI Indicator MT4 – Faster but noisier than TSI
- Awesome Oscillator MT4 – Bill Williams’s momentum histogram
- Best Oscillator Indicators for MT4
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