Better Overbought Oversold Indicator for MT4 and MT5

Written by Dominic Walsh · Published 29 Jul 2026 · Last updated 18 Sep 2026

Entering an extreme zone only says a move has stretched. Leaving one says the stretching stopped. The better overbought oversold indicator marks that second event, which is the difference the name points at. Its reading smooths where each close sits inside a twenty-one bar range.

This build ships as a compiled .ex4 for MT4 and .ex5 for MT5; the screenshots below come from EURUSD H1.

Platforms	MT4 (.ex4) + MT5 (.ex5)
Chart window	Separate window (levels 20 / 50 / 80)
Plots	3: OB/OS Oscillator, Leave Oversold, Leave Overbought
Alerts	popup, push notification, email, sound
Inputs	10

Plots, colours and placement

One line and two marks in the pane.

`OB/OS Oscillator` runs aqua at width 2.

`Leave Oversold` uses arrow 233 in lime.

`Leave Overbought` uses arrow 234 in red.

Levels sit at twenty, fifty and eighty.

The scale runs zero to one hundred and stays there.

• OB/OS Oscillator: line, aqua, width 2
• Leave Oversold: arrow, lime, width 2, arrow code 233
• Leave Overbought: arrow, red, width 2, arrow code 234

What feeds each plot

Position in the range

`InpPeriod` `21` bars give a highest high and a lowest low. Where the close sits between those two, as a percentage, is the raw reading.

One smoothing pass

Raw values jump on every bar. `InpSmooth` `3` averages them, which steadies the line without pushing it far behind price.

Leaving, not entering

The mark needs two bars. The previous one has to sit inside a zone and the current one outside it. Entering a zone prints nothing at all.

How to read it

Above `InpOverBought` `80.0` closes sit near the top of the range.

Below `InpOverSold` `20.0` they sit near the bottom.

Fifty is the middle of the window.

A mark says the reading has just left a zone.

The reading can stay inside a zone for a long run.

Twenty-one bars is a little longer than the usual fourteen.

Alert channels in this build: popup, push notification, email and sound, one message per closed bar.

`EnableAlerts` covers the zone-exit alerts and starts true with `EnablePopup`. `EnablePushNotify` reaches a phone, `EnableEmail` posts mail and `EnableSound` plays `SoundFile`. Those three begin off, and exits report once a bar.

Every Better Overbought Oversold Indicator input

Core settings

Setting	What it does	Default
InpPeriod	Range look-back (n bars). Bars in the range window, `21`.	21
InpSmooth	Smoothing SMA. Bars in the smoothing pass, `3`.	3
InpOverBought	Overbought zone. Upper zone edge, `80.0`.	80.0
InpOverSold	Oversold zone. Lower zone edge, `20.0`.	20.0

Alert settings

Setting	What it does	Default
EnableAlerts	Master switch, `true`.	on
EnablePopup	Box in the terminal, `true`.	on
EnablePushNotify	Buzz on a phone, `false`.	off
EnableEmail	Mail on a zone exit, `false`.	off
EnableSound	Cue on a zone exit, `false`.	off
SoundFile	Which clip plays, `”alert.wav”`.	alert.wav

Where to run it

Twenty-one bars covers about a session on an hourly chart. EURUSD H1 is the reference chart. Zone exits come a few times a week there. On M5 the line crosses the zones all day. On daily bars each exit covers a month.

What this one cannot tell you

A bounded reading pins at an extreme through a trend.

Leaving a zone can happen mid-move rather than at a turn.

One outsized bar sets the range for twenty-one bars.

A single smoothing pass still leaves the line jumpy on fast charts.

Copy the compiled Better Overbought Oversold Indicator file into your MQL4/Indicators folder, and the MT5 build into MQL5/Indicators, then restart the terminal and drag it onto a chart. The step-by-step guide with screenshots is at how to install MT4 and MT5 indicators.

Download the Better Overbought Oversold Indicator for MT4 and MT5

The zip holds the compiled Better Overbought Oversold Indicator build for MT4 and MT5, plus a short README. Compiled files only, no source. Enter your email below and the download link arrives in your inbox.

FAQ

Why does Leave Oversold mark an exit, not entry?

Because entering an extreme only says the move has stretched, and it can hold there for many bars. Leaving the zone marks where that stretching stops, which arrives later but says more.

What does InpPeriod 21 measure?

The highest high and the lowest low of the last twenty-one bars. It then places the close as a percentage between those two, so the reading describes position in the recent range and nothing else.

Is InpSmooth 3 enough smoothing?

Three bars is a deliberate compromise. It steadies the raw reading without the lag a longer pass adds. On a fast chart the line still moves sharply, which is the cost of staying responsive.

Can the reading sit above InpOverBought for long?

Yes, and that is the main thing to expect. In a sustained trend closes stay near the top of every window, so the line can hold above eighty for dozens of bars without any mark printing.

Are results guaranteed?

No. Trading involves risk. Results are not guaranteed; past performance is not indicative of future results. Use the Better Overbought Oversold Indicator as one input. Always backtest before trading live.