Trends/Trend strength and direction

Vortex indicator

Two lines that compare the size of up swings and down swings over 14 bars.

Trend strength and directionBest on 6M, 1YAlso called VI

Illustration of the vortex indicator shape. It is a sketch, not real price data.

What it shows

The Vortex indicator by Etienne Botes and Douglas Siepman sums two kinds of movement over 14 bars: the distance from today's high to yesterday's low (VM+) and from today's low to yesterday's high (VM−). Each is divided by the true range.

VI+ above VI− means upward swings have been larger.

How we find it

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

VM+ = |high − previous low|. VM− = |low − previous high|.
Sum each over 14 bars.
Divide each by the sum of true range.
Plot VI+ and VI−.

Starting values: Length 14. These are proposed and will be tuned on real price data before launch.

How to read it

Teal line is VI+. Red line is VI−.
They cross at the gold dot.
Values near 1 are the typical level.

Status labels you may see

Label	What it means
VI+ above VI−	Up swings larger.
VI− above VI+	Down swings larger.
Just crossed	Cross in the last 3 bars.

What cancels it

A cross flips the state.

What traders check next

Gap between the lines.
ADX.
Price trend.

Limits

Newer indicator.
Lags.
Many crosses in sideways periods.

Try it in forecastviz

Open any ticker and choose Trend strength and direction → Vortex indicator in the left menu.
Switch between 6M, 1Y to see how the picture changes.
Compare with DI crossover and Average directional index on the same chart.

Open on a ticker

Questions

Why 'vortex'?

The authors drew on the idea of rotating flows.

Is it like DI?

Similar idea. Different formula.