TSI Indicator: Formula, Settings and How to Read It
TSI, the True Strength Index, double-smooths close-to-close momentum and divides it by the same double smoothing of absolute momentum, producing a signed line expressed in percent. The default smoothing lengths are 25 for the long pass and 13 for the short one.
Senzoukria · Indicators · Updated September 2026
TSI ships with the Senzoukria desktop app, in the Momentum group of the indicator catalogue. It is drawn in its own panel below the chart.
What TSI measures
Momentum is simply each close minus the previous one. The numerator applies the long exponential average and then the short one to that signed series; the denominator applies exactly the same pair to the series with its sign removed. The ratio therefore reports what share of recent movement went in one direction: near +100 nearly every smoothed change was upward, near -100 nearly every one was downward, and near 0 gains and losses have cancelled out. Each exponential average is seeded with a simple moving average, so the line begins only once both passes have enough history. If the denominator is zero, which requires the market to have been flat across the whole smoothing memory, no value is produced.
The formula, as implemented
This is not a description of how the indicator is usually defined elsewhere — it is what the shipped code computes, documented next to the implementation:
TSI (Blau) — double lissage EMA du momentum (graine SMA, cf. en-tête) : mtm = close − closeₚ TSI = 100 · EMA_short(EMA_long(mtm)) / EMA_short(EMA_long(|mtm|)) Dénominateur nul (marché plat sur toute la mémoire du lissage) → null. Défauts 25/13 (Blau).
How to read it
- The sign tells you which direction net smoothed momentum has taken; a crossing of the zero line marks the point where the two cancel.
- The magnitude describes consistency, not size. A steady one-tick drift in a single direction can push TSI high, while an alternating sequence of large bars keeps it near zero.
- The slope usually turns before the sign does, because the ratio has to travel back through zero after momentum reverses.
- A divergence between price and TSI says the newer leg was made of less one-sided changes than the earlier one; it does not say when the move ends.
- No fixed overbought level is defined here. Compare the current reading against the range the same instrument has produced on the same bar type.
Parameters and defaults
The long smoothing of 25 is applied first and does most of the filtering; the short smoothing of 13 is applied to its output. Raising either lengthens the memory and pushes turns further out. Both accept 1 to 200, and the usual arrangement keeps the short value below the long one, although nothing in the settings enforces it.
| Parameter | Type | Default | Range |
|---|---|---|---|
| Long smoothing | number | 25 | 1 – 200 |
| Short smoothing | number | 13 | 1 – 200 |
What it does not show
Two exponential passes mean the line confirms a change of direction late; that is the price of its smoothness. It consumes closes only, so the path taken inside each bar is invisible to it, as is the question of which side was hitting the book. On futures contracts a session gap enters as a single large momentum value and keeps affecting both averages for many bars. And because the output is a ratio, magnitude is normalised away: a quiet trend and a violent one can settle at the same reading.
Using it in Senzoukria
Add it from the Indicators panel of any footprint chart or candle chart. It runs on futures data from Rithmic or Databento and on crypto pairs from Binance and Bybit, on the same engine — the calculation does not change with the venue, only the data feeding it does. Market data subscriptions are billed by the provider, separately from the app.
Related indicators
- Williams %R — Momentum
- Momentum — Momentum
- MFI — Momentum
- ADX/DMI — Momentum
- Vortex — Momentum
- Linear Regression Slope — Momentum
See the full indicator library, or start with the order flow guide if you are new to reading aggression, delta and absorption.
Frequently asked questions
- Why can TSI read high while the price move is small?
- Because the ratio compares smoothed net momentum with smoothed absolute momentum. If every change over the smoothing memory went the same way, the two are nearly equal and the reading approaches 100, whether those changes were one tick each or twenty. The value measures one-sidedness, not distance.
- What TSI settings should I use?
- The defaults are 25 for the long smoothing and 13 for the short one, the lengths Blau published. Shorter values follow price more closely and cross zero more often; longer values produce fewer turns and confirm them later. The trade-off is between reactivity and noise, and it depends on the bar interval you work on.
- Is TSI the same as MACD?
- No. MACD is the difference between two exponential averages of price, so its scale depends on the instrument. TSI divides smoothed momentum by smoothed absolute momentum, which bounds it between -100 and +100 and makes readings comparable from one instrument to another.