Donchian Channels

What are Donchian Channels?

Donchian Channels are a price channel that marks the highest high and lowest low over a lookback of N bars, with a midpoint, also called the midrange, halfway between those two boundaries. The bands turn a window’s extremes into explicit breakout and exit levels: under the prior-bar convention, a close above the upper band exceeds every high in that window.

This entry uses the preceding N completed bars, excluding the current bar. That convention creates a fixed reference for evaluating a breakout during the current bar.

How are Donchian Channels calculated?

Upper = maximum high of the prior N bars. Lower = minimum low of the prior N bars. Midpoint = (upper + lower) / 2.

The worked example uses N = 10. An upper band of $52.60 and lower band of $50.20 give midpoint $51.40 and width $2.40. Width is approximately 4.67% of the midpoint.

The midpoint averages the two extremes. It is not the average of every price in the window.

Donchian breakout timing: prior-bar vs current-inclusive

The current bar closes at $53.60, which exceeds the prior upper band by $1. Its high is $53.80.

The prior-bar upper channel remains $52.60 during this breakout bar. On the next bar, the completed $53.80 high enters the window and becomes the new upper level.

A current-inclusive channel instead contains the current high and low. To apply the same breakout rule to that display, compare price with the previous completed channel value.

How the bands change as the window rolls

A boundary stays fixed while the same extreme remains selected. It changes when a more extreme observation enters or when the selected extreme leaves the window.

In the chart, the lower band remains $50.20 through bar 25. It rises to $50.32 at bar 26 as the older low drops out. A closer exit reference therefore does not require a new high or low on the current bar.

A close-only channel uses a different input. Its upper boundary is no higher than the high-based boundary over the same bars, and its lower boundary is no lower than the low-based boundary. Define that variant explicitly when using it.

Donchian channel entry and exit rules

Choose an intrabar break or a completed-close break. Then specify execution, position size and invalidation. An example long rule enters above a prior-20-bar high and exits below a prior-10-bar low.

If the stop must only tighten, apply an explicit ratchet to its candidate level. Use the planned entry-to-stop distance when sizing the position.

Read the width as the price span of the selected historical window, and use the options model’s own horizon and volatility inputs when comparing contracts around the setup. For the options side, Options Flow shows the large orders in the ticker and the Options Profit Calculator compares structures around the target and expiration in the plan.

Limitations of Donchian Channels

• Check which bar sets each band. The bands react only to extremes: one spike bar sets a boundary for the whole lookback, and the band jumps when that bar leaves the window, even with no new high or low.
• Test the lookback on the instrument and interval you trade. A 20-bar and a 55-bar channel can give different breakout points on the same chart.
• Size each entry for a run of false breaks in a sideways market. Price can close beyond a band and then fall back inside, so a breakout rule can produce a run of losing entries.
• Match the window convention and input before comparing platforms. Prior-bar or current-inclusive windows and high-low or close-only inputs can change both the bands and the signals.
• Width measures the range of past bars, so size stops for the range the market is making now. Compare it with a declared price scale or historical range.

Bottom line

Donchian Channels turn a window’s highest high and lowest low into explicit breakout and exit levels. Fix the window convention, lookback and trigger before trading them, and size each position from the distance between the entry and the exit band.