Trends/Momentum oscillators

True strength index

A smoothed measure of momentum scaled between −100 and +100.

Momentum oscillatorsBest on 6M, 1YAlso called TSI

Illustration of the true strength index shape. It is a sketch, not real price data.

What it shows

William Blau's TSI takes the change in price each bar and smooths it twice with EMAs (25 then 13). It does the same to the absolute change, then divides one by the other and multiplies by 100.

The double smoothing gives a line with less noise than most momentum measures, which crosses zero less often.

How we find it

The same code that draws it on your chart follows these steps, with the same result every time.

Price change = close − previous close.
Smooth the change with EMA(25), then EMA(13).
Smooth the absolute change the same way.
TSI = 100 × smoothed change ÷ smoothed absolute change.

Starting values: Long 25; Short 13; Signal 7. These are proposed and will be tuned on real price data before launch.

How to read it

The panel shows TSI.
The dashed line is zero.
The curve is smoother than RSI.

Status labels you may see

Label	What it means
Above zero	TSI is above zero.
Below zero	TSI is below zero.
Near zero	TSI between −5 and 5.

What cancels it

Nothing cancels it.

What traders check next

Signal line crosses.
Compared with its own range.
Price trend.

Limits

More lag, because of two smoothings.
Settings change a lot.
Not widely standard.

Try it in forecastviz

Open any ticker and choose Momentum oscillators → True strength index in the left menu.
Switch between 6M, 1Y to see how the picture changes.
Compare with Relative strength index and MACD on the same chart.

Open on a ticker

Questions

Why smooth twice?

To remove noise while keeping the shape.

Is it better than RSI?

Different. It is smoother and lags more.