Session ATR Reversal Zones

Session ATR Zones

Session-based ATR levels projected from each session’s open: Asia, London and New York.

Overview

Session ATR Zones plots volatility-based price zones for each major trading session. Instead of using a single daily ATR for the whole day, it calculates a separate ATR for each session (Asia, London, New York) and projects levels above and below that session’s open price. This gives you a realistic picture of how far price typically travels during a specific session.

How It Works

1. For each session, the indicator reads intraday bars and finds the session’s open, high, low and close.
2. The session range (High – Low) is used as the “True Range” for that session.
3. A session ATR is calculated from the previous sessions only, so no future data leaks into today’s levels.
4. Levels are drawn at 100%, 75%, 50% and 25% of the session ATR, above and below the session open.

Key Features

• Three independent sessions: Asia, London and New York, each with its own on-chart toggle button.
• Robust ATR calculation: Wilder-smoothed ATR, seeded with the median of the first N values, with outlier clipping (TR is capped at N × the median of recent values) so one extreme session doesn’t distort the levels.
• Automatic server time handling: Enter your broker’s standard GMT offset and choose the DST rule (US, EU or none). Session hours are entered in GMT and converted automatically.
• Live offset check: Warns you on the chart if the calculated server offset differs from the live offset, so you can spot a wrong DST setting immediately.
• Data quality filters: Sessions with too few intraday bars, or a late first bar, are skipped instead of producing misleading levels. The chart status line shows how many sessions were dropped.
• Live extension: Today’s running session lines grow to the current time (optional).
• Lightweight: Full rebuild only on a new day, and live updates only on a new intraday bar.
• Customizable look: Upper/lower level colors, label font size, label history, and lines drawn behind candles.

Inputs

ATR – General

• ATR_Period : ATR period (default 14)
• InpWarmupMult : extra D1 history used for warm-up
• InpOutlierMult : outlier clipping multiplier (0 = off)
• DaysToShow : number of historical days to draw
• ShowLevelLabel / InpLabelDays / InpFontSize : label controls
• InpLinesInBackground , InpGrowToNow : display options

Server Time & DST

• InpServerGMTStd : broker’s standard (winter) GMT offset, usually GMT+2
• InpDSTMode : US DST, EU DST or no DST

Intraday Data Quality

• InpMinCoveragePct : minimum bar coverage inside the session window
• InpMaxStartGapMin : maximum gap between session start and the first bar
• InpIntradayTF : intraday timeframe for session data (default M15)

Sessions (GMT hours)

• Start/end hour and initial visibility for Asia, London and New York (defaults: 0–8, 8–16, 13–21)

Setup Tips

• Set InpServerGMTStd and InpDSTMode to match your broker. Most FX brokers use GMT+2 in winter with US DST.
• Make sure intraday history is downloaded for the chosen timeframe (M15 by default) so enough days are available.
• Session hours must be within a single day (0 ≤ start < end ≤ 24). Overnight sessions are not supported.
• Works on any timeframe and any symbol, but is best suited to FX, indices and metals with clear session behavior.

Usage Ideas

• Use the 50% and 75% levels as potential intraday targets or reaction areas.
• Treat the 100% level as a sign of an extended session move.
• Compare the ATR zones of different sessions to see which one is the most volatile for your instrument.

Notes

• The indicator draws objects only (no buffers). All objects are removed when the indicator is deleted.
• Levels are a statistical reference of typical movement, not a guarantee of price behavior. Always combine them with your own analysis and risk management.