Keltner breakout buy sell

Marks closes outside the Keltner channel: buy above the upper band, sell below the lower band.

The middle line is an exponential average of closes over ema_window bars. The upper and lower bands sit mult times a smoothed average true range (atr_window bars) above and below it, so their width follows recent bar ranges. A buy marks a bar whose close is above the upper band and a sell marks a bar whose close is below the lower band. It is a breakout test against volatility-scaled bands, not a crossover, and the chart shows only the markers, not the bands.

How to read it

Buy markers sit on candles that close above the upper band; sell markers sit on candles that close below the lower band.
The band lines are not drawn, so judge each marker against the candle and the recent range.
A run of consecutive markers means price kept closing outside the band; the first marker of a run is the breakout bar.
Buy and sell are independent, so a sell marker does not cancel an earlier buy.

What it outputs

Buy (above upper band): Marks each bar whose close is above the upper band. An upward breakout out of the volatility channel, not a reversal call.
Sell (below lower band): Marks each bar whose close is below the lower band. A downward breakout; the name does not mean go short.

When it fires

A buy fires on each bar whose close is above the upper band, and a sell on each bar below the lower band. Each run of such bars is one episode. With confirm_days above 1, the marker fires once per run, on the bar the run reaches that length.

Settings

ema_window: Length of the average the bands are centred on. Shorter tracks each swing, so the middle moves with price. Longer lags, so in a sustained move price runs further from the middle before a breakout.
atr_window: Bars used to measure the typical bar range that sets the band width. Shorter reacts within a few bars and widens or narrows the bands quickly. Longer changes the width slowly.
mult: How many ATRs the bands sit from the average. Higher widens the channel and cuts markers; lower narrows it and adds them. At 0 both bands sit on the average. Below 0 the bands swap sides and markers lose their breakout meaning.
band: Fraction of the band level that price must clear, applied to each band. Positive values move both thresholds out and cut markers; negative values pull them in. At -1 both signals fire on every bar; at 1 neither fires.
confirm_days: Consecutive bars the close must stay beyond a band before a marker appears. Higher values drop brief pokes outside the band and move the marker to the bar where the run reaches that length.

Pitfalls

Frequent at defaults: on SPY one-minute bars for September 2026 it marked about 30 buy and 28 sell episodes a day, so the chart is busy. Raise mult or confirm_days to thin them.
The current bar is part of both the average and the true range, so a sharp bar widens the band it is tested against on that same bar and can fail to break out.
Parameter ranges allow broken settings: at band -1 both signals fire on every bar, and at mult below 0 the bands swap sides.