Accumulation/Distribution Line (A/D Line)

A cumulative volume indicator weighted by where the close fell within the bar's range. More nuanced than OBV — but the same confirmation role.

IndicatorBy AlgoLiftUpdated 5 min read
On this page 13What it measuresFormulaInputs in AlgoLiftRecommended settingsOutputs in AlgoLiftHow to read itBest in / worst inThree confirmation patterns1. Trend confirmation2. Breakout confirmation3. Hidden accumulation detectionAdvanced patterns in AlgoLiftCommon mistakes

A cumulative volume indicator where each bar's contribution is weighted by where the close fell within the bar's high-low range — closes near the high count as accumulation, closes near the low count as distribution. More nuanced than OBV because a doji bar (close near middle) contributes near-zero, but the same confirmation-tool role.

What it measures

  • Quality-weighted cumulative volume. Volume × (close's position within the high-low range). A bar that closes near its high adds positive flow; a bar that closes near its low adds negative flow.
  • Hidden accumulation/distribution. Detects when institutions are quietly accumulating or distributing — the close-position weighting captures this better than OBV's bar-direction-only approach.
  • Trend confirmation via slope. Like OBV, the A/D Line's trajectory matters more than its absolute value.

Formula

Inputs in AlgoLift

SettingDefaultRangeNotes
Smoothing Period101–200EMA period for the smoothed line. Set to 1 to read the raw cumulative line.
  • 10 (default): Standard smoothing — clean enough for trend reading.
  • 5: Faster — for short-timeframe trading.
  • 20–30: Slower — emphasizes only major flow changes.

Outputs in AlgoLift

HandleTypePlottedNotes
A/D Line (Raw)NumericAlwaysCumulative running total.
A/D Line (Smoothed)NumericAlwaysEMA-smoothed version — the primary reading.
Slope (Smoothed)NumericOn selectRate of change of the smoothed line.
Raw Money FlowNumericOn selectPer-bar Money Flow Volume — useful for inspection.

How to read it

  • A/D Line rising: Accumulation in progress — closes near highs are dominating, volume confirms upside.
  • A/D Line falling: Distribution in progress — closes near lows dominate.
  • A/D Line flat during a price rally: Bars are closing near midpoints despite price moving up — a warning that the rally lacks decisive participation.
  • Divergence between A/D Line and price: Same interpretation as OBV divergence — often precedes reversals.

A/D Line generally produces fewer false signals than OBV in choppy markets because the CLV weighting filters out indecisive bars. In trending markets, the two indicators usually agree.

Key Takeaway

A/D Line is OBV with quality-weighting. Where OBV asks "did the bar close up or down?", A/D Line asks "how decisively?" In markets where bars frequently close near their midpoints (chop), A/D Line is the more reliable read. In strong trends, OBV and A/D Line agree.

Best in / worst in

Best in trending markets and as a confirmation indicator for breakouts. The close-location weighting makes A/D Line particularly good at distinguishing strong trend moves (decisive closes) from weak ones (closes near midpoints).

Worst in instruments with frequent gaps — the CLV calculation can produce extreme single-bar values when high-low range is large. Also weak on very-low-volume instruments where the cumulative sum doesn't have enough data to be meaningful.

Three confirmation patterns

1. Trend confirmation

Validate trends from price-based systems.

  • Valid long trend: Price > EMA(50) AND A/D Line slope > 0.
  • Valid short trend: Price < EMA(50) AND A/D Line slope < 0.
  • Suspect trend: Price moving but A/D slope flat → skip new entries.

2. Breakout confirmation

Filter breakouts by A/D agreement.

  • Valid upside breakout: Price closes above a 20-bar high AND A/D Line (Smoothed) is making a new 20-bar high too.
  • Failed breakout: Price makes new high but A/D doesn't → high probability of mean reversion.

The close-location weighting catches "breakouts" where price hit the level but closed weakly — exactly the kind of false breakout that retail strategies often chase.

3. Hidden accumulation detection

When price is consolidating but A/D Line is rising, institutions may be quietly accumulating.

  • Setup: Price has been within 2% of its 30-bar mean for at least 20 bars (consolidation).
  • Long signal: A/D Line has made a new 30-bar high during the consolidation → arm a long entry on the first close above the consolidation range.

A pattern that picks up moves before price confirms them.

Advanced patterns in AlgoLift

A/D Line + price divergence with BarsAgo Modifier. Wire Price > Price 10 bars ago AND A/D Line < A/D Line 10 bars ago — captures bearish divergence directly. Pair with a regime filter (KAMA ER < 0.3) for high-conviction counter-trend entries.

A/D Slope as a scaled-entry confirmation. Take initial position on a price-based system. Use Scale-In Entry to add only when A/D Slope confirms the direction. Volume-quality-confirmed scaling.

Raw Money Flow for individual bar analysis. The per-bar Money Flow Volume output lets you set up a Tally over the last N bars — "how many of the last 10 bars had strongly positive money flow?" is a direct measure of recent buying conviction.

Cross-instrument A/D for portfolio context. Compute A/D Line on a benchmark instrument (e.g., SPY) alongside an individual symbol via separate Data Source nodes. When the symbol's A/D outperforms the benchmark's, the stock is relatively strong. See the multi-series Visual Builder pattern.

Common mistakes

  • Treating A/D Line and OBV as interchangeable. They measure different things. OBV uses bar-direction; A/D Line uses close-location. They often agree but the disagreements are informative.
  • Reading the absolute value. Like OBV, A/D Line drifts to arbitrary numbers. Trajectory matters, value doesn't.
  • Using on gap-prone instruments without adjustment. A single gap-and-fill bar can produce an extreme Money Flow Volume reading that distorts the cumulative line. Apply session filters or use the smoothed output to dampen these.
Common Misconception
Myth
A/D Line is just a slower OBV.
Reality
They have different inputs. OBV adds full volume on any up-bar; A/D Line weights by *where in the range* the bar closed. A doji on heavy volume contributes near-zero to A/D Line and full volume to OBV. In choppy markets where many bars close near midpoints, the two indicators diverge meaningfully — and A/D Line is usually the more honest read.