Vertical Horizontal Filter

What is the Vertical Horizontal Filter?

The Vertical Horizontal Filter (VHF) is a trend-versus-range gauge built on a simple geometric idea: in a trend, price movement is mostly vertical (net progress), while in a range it is mostly horizontal (back-and-forth travel with little progress). The VHF captures this as a ratio, dividing the distance between the highest and lowest close over a window by the total distance price actually traveled bar to bar. A market that walks in a straight line scores near 1; a market that churns scores near 0.

The indicator is attributed to Adam White, who presented it in the early 1990s as a way to decide which category of tool to trust: trend-following indicators when the VHF is high and rising, and oscillators when it is low or falling. That routing role, rather than signal generation, remains its main job.

The same efficiency intuition appears elsewhere in technical analysis, most directly in the Kaufman efficiency ratio, which uses net close-to-close change instead of the extreme-to-extreme range. Traders keep the VHF around because it is transparent, cheap to compute, and answers the single most consequential question in system design: is this market currently trending at all?

How it's calculated

Net range over the window is divided by the summed absolute bar-to-bar changes over the same window.

Some implementations use highest high and lowest low instead of closes in the numerator; the reading is slightly noisier but the interpretation is unchanged.

The VHF has no fixed trend threshold; it is usually read relative to its own recent history.

How traders use it

• As an indicator selector: a high or rising VHF argues for acting on moving average and breakout signals, while a low or falling VHF argues for fading extremes with oscillators. This routing decision is its designed purpose.
• As a filter inside a single system: trend entries are only taken when the VHF exceeds a level such as its own moving average or a percentile of recent readings, which tends to cut whipsaw trades at the cost of later entries.
• As a slope signal: because absolute levels vary by market, many practitioners watch the direction of the VHF rather than its value, treating a rising line as trend development regardless of where it starts.
• Its limitations are direction-blindness and lag: the VHF cannot distinguish an uptrend from a downtrend, and by the time a 28-bar ratio confirms trending conditions, a meaningful part of the move has often passed. Pairing it with a directional tool such as the ADX/DMI system or a moving average is standard practice.

VHF vs neighboring efficiency and strength measures