Directional Movement Index DMI
The +DI and −DI lines that reveal which side — buyers or sellers — controls the trend.
Quick Answer
The Directional Movement Index plots +DI and −DI to show whether up or down movement dominates; +DI above −DI is bullish and the reverse bearish. Plotted with ADX, it separates direction from strength. On Nifty, a +DI/−DI crossover flags a possible trend change, but crossovers whipsaw in sideways markets without ADX confirmation.
Directional Movement Index: key takeaways
The DMI is Wilder's directional compass: +DI above −DI means buyers control the trend, −DI above +DI means sellers do, and the crossover flags the handover. But direction is only half the story — pair it with ADX so you act on crossovers only when the trend is genuinely strong, or the DI lines will whipsaw you in every range.
Directional Movement Index at a glance
| Category | Trend Strength Indicators |
|---|---|
| Type | Lagging trend-direction and strength system |
| Created by | J. Welles Wilder Jr. (1978) |
| Best timeframe | Daily for swing trades; 15–30 min for intraday |
| Best settings | 14 periods (Wilder default), filtered by ADX above 20–25 |
| Settings to avoid | Trading every DI crossover regardless of ADX or trend context |
| Works best in | Trending markets with a clear directional winner |
| Struggles in | Tight ranges where the DI lines tangle |
Directional Movement Index in simple words
The DMI is Wilder's directional system. It plots two lines: +DI, which measures how strong the upward movement is, and −DI, which measures the downward movement. When +DI is above −DI, buyers are in control; when −DI is above +DI, sellers are. A crossover of the two lines flags a change in who is winning. The DMI is almost always shown together with ADX, which turns the same data into a single strength reading, so the pair tells you both the direction and the force of a trend.
Directional Movement Index — visual
How Directional Movement Index looks on a chart
Directional Movement Index: professional explanation
How +DI and −DI are built
Each bar has a directional movement. If today's high extends above yesterday's high more than today's low drops below yesterday's low, the bar has positive directional movement (+DM); the reverse gives negative (−DM). Wilder smooths +DM and −DM over 14 periods and divides each by the smoothed True Range to get +DI and −DI as percentages. So +DI is the share of range attributable to up-moves, −DI the share from down-moves.
Crossovers as directional signals
The core DMI signal is the crossover. When +DI crosses above −DI, upward movement has overtaken downward — a bullish directional shift. When −DI crosses above +DI, the opposite. Wilder's own rule was to buy on a +DI cross using the signal bar's high as the trigger and stop. These crossovers are cleaner in trending markets and noisy in ranges, which is why ADX is used to gate them.
The spread between the lines
The distance between +DI and −DI matters as much as the cross. A wide and widening spread means one side is decisively in control — a strong, clean trend. A narrow spread with the lines weaving around each other means the market is directionless. This spread is exactly what ADX distils into a single number, which is why the DMI and ADX are read together.
Why DMI needs ADX
The DI lines answer 'which way?' but not 'how strongly?'. In a tight range +DI and −DI cross back and forth constantly, generating false directional signals. ADX solves this: only when ADX confirms a strong trend (above 20–25) are the DI crossovers worth acting on. Direction without strength is a recipe for whipsaws, so the two halves of Wilder's system are designed to be used as one.
Directional Movement Index formula
Directional Movement Index formula
+DI = 100 × Smoothed(+DM) / ATR; −DI = 100 × Smoothed(−DM) / ATR
+DM and −DM are the directional movements per bar, smoothed with Wilder's averaging over N (default 14), and divided by the Average True Range. ADX is derived from the difference between +DI and −DI.
- +DM — Positive directional movement — the excess of today's high over yesterday's high, when it exceeds the downward move
- −DM — Negative directional movement — the excess of yesterday's low over today's low, when it exceeds the upward move
- ATR — Average True Range — Wilder-smoothed True Range, used to normalise +DM and −DM
- N — Look-back period, default 14 bars
How Directional Movement Index is calculated
- For each bar, compute the up-move (today's high − yesterday's high) and the down-move (yesterday's low − today's low).
- Assign +DM to the larger up-move if it is positive and exceeds the down-move; assign −DM to the larger down-move in the opposite case; otherwise both are zero.
- Smooth +DM, −DM and True Range with Wilder's averaging over N periods.
- Compute +DI = 100 × smoothed +DM / smoothed TR, and −DI = 100 × smoothed −DM / smoothed TR.
- Read +DI above −DI as bullish control and −DI above +DI as bearish; watch for crossovers and the spread, ideally filtered by ADX.
Directional Movement Index: interpretation & signals
Traders read the DMI for direction: +DI above −DI means buyers dominate, −DI above +DI means sellers do. Crossovers flag directional shifts, the spread shows conviction, and ADX (its companion) confirms whether the shift is strong enough to trade.
Buy / bullish signals
- +DI crosses above −DI, signalling upward movement has taken control.
- +DI crosses above −DI while ADX is above 20–25, confirming a strong bullish shift.
- The +DI/−DI spread widens with +DI on top, showing the uptrend is gaining conviction.
- In an uptrend, −DI dips and +DI holds above it after a pullback (trend continuation).
Sell / bearish signals
- −DI crosses above +DI, signalling downward movement has taken control.
- −DI crosses above +DI while ADX is above 20–25, confirming a strong bearish shift.
- The spread widens with −DI on top, showing the downtrend is strengthening.
- In a downtrend, +DI fails to reclaim −DI after a bounce (trend continuation).
False signals to beware
- In a range, +DI and −DI cross back and forth repeatedly, producing whipsaw signals — the reason ADX gating is essential.
- Crossovers can occur well after the move has begun because the DI lines are smoothed.
- A crossover with a very narrow spread and low ADX rarely holds.
Directional Movement Index: advantages & limitations
Advantages
- Gives an objective read on which side — buyers or sellers — controls the market.
- The spread between the lines shows the conviction behind a trend.
- Pairs seamlessly with ADX for a complete direction-plus-strength system.
- Crossovers provide clear, rule-based entry and exit points in trends.
Limitations & disadvantages
- DI crossovers whipsaw badly in ranging markets without an ADX filter.
- Lags because the DI lines are Wilder-smoothed.
- Two lines plus ADX can look cluttered to beginners.
- Direction alone is unreliable — it must be combined with strength.
Combining Directional Movement Index with other indicators
- Average Directional Index — The DI lines give direction and ADX grades strength; take DI crossovers only when ADX confirms a strong trend — this is Wilder's intended combination.
- Average True Range — ATR, which underpins the DI calculation, also sizes stops for DMI-based trend entries.
- Moving Average — A moving-average trend filter keeps you taking only the DI crossovers aligned with the larger trend, cutting counter-trend whipsaws.
Directional Movement Index: practical examples (Nifty & Bank Nifty)
NIFTY example
Nifty has been falling and −DI is above +DI. As Nifty bases and turns up, +DI climbs and crosses above −DI while ADX is at 22 and rising through 25. That +DI crossover, confirmed by a rising ADX above 25, is the DMI's textbook bullish signal — direction (the cross) plus strength (ADX) together tell a trend-follower the up-move is real, not a range bounce.
BANKNIFTY example
Bank Nifty is stuck in a tight consolidation and its +DI and −DI lines cross each other four times in a week while ADX languishes at 14. A trader who acts on each DI crossover is whipsawed repeatedly. The correct read is that ADX below 20 invalidates the DI signals — the lines are tangled because there is no trend, so the DMI is saying 'stand aside' until ADX confirms a directional winner.
Common misconceptions about Directional Movement Index
- Misconception: DMI and ADX are the same indicator under two names.
Reality: Not exactly — they are companions. The DMI refers to the +DI and −DI directional lines, while ADX is the strength line built from them. Many charting platforms plot all three together and label the whole thing DMI or ADX interchangeably.
Common mistakes with Directional Movement Index
- Trading DI crossovers without checking ADX — the classic whipsaw trap in ranges.
- Reading +DI/−DI as overbought/oversold levels; they show direction, not extremes.
- Ignoring the spread between the lines, which signals conviction.
- Expecting the crossover to be early — the DI lines are smoothed and lag.
How professionals use Directional Movement Index
Professionals treat the DMI and ADX as a single instrument. They use the DI crossover and the DI spread to identify which side controls the market and how decisively, but they only act when ADX confirms the trend is strong enough. In systematic trend strategies a +DI/−DI cross is often one directional input combined with an ADX strength gate and a higher-timeframe filter, never a standalone trigger — because the whole point of Wilder's system is that direction and strength must agree.
Directional Movement Index: frequently asked questions
What is the DMI indicator?
The Directional Movement Index is a system created by J. Welles Wilder in 1978 that plots +DI and −DI lines to show whether upward or downward movement dominates. It reveals trend direction and is usually shown with ADX, which measures the trend's strength.
What is the difference between +DI and −DI?
+DI measures the strength of upward price movement and −DI the strength of downward movement. When +DI is above −DI, buyers control the trend; when −DI is above +DI, sellers do. Their crossover signals a change in control.
How is DMI different from ADX?
They are two parts of the same system. The DMI is the +DI and −DI lines that give direction; ADX is a single line derived from them that grades strength. DMI says which way, ADX says how strongly.
What is a DMI crossover?
A DMI crossover is when +DI and −DI cross. +DI crossing above −DI is a bullish directional signal; −DI crossing above +DI is bearish. Crossovers are most reliable when ADX confirms a strong trend.
What are the best DMI settings?
The standard is 14 periods, following Wilder's original design. The DI lines are then usually filtered by requiring ADX above 20–25 before acting on a crossover, to avoid whipsaws in ranging markets.
Is DMI a leading or lagging indicator?
DMI is a lagging indicator because the +DI and −DI lines are smoothed with Wilder's averaging. Crossovers can occur after a move has begun, so they are best used with confirmation rather than as early signals.
Why does DMI whipsaw?
In ranging markets +DI and −DI stay close together and cross back and forth repeatedly, generating false signals. This is why the DMI should be filtered by ADX — only crossovers occurring while ADX is above 20–25 are considered reliable.
Can DMI be used for Nifty and Bank Nifty?
Yes. The DMI works on any liquid instrument. On Nifty and Bank Nifty it is valuable for reading directional control, but because both alternate between trends and ranges, the ADX filter is important to avoid whipsaws.
Directional Movement Index: voice-search questions
Natural-language questions people ask about Directional Movement Index.
What is DMI in simple words?
DMI plots two lines: a plus line for upward strength and a minus line for downward strength. When the plus line is on top, buyers are winning; when the minus line is on top, sellers are winning.
Is a DI crossover a buy signal?
A +DI crossing above −DI can be a buy signal, but it is only reliable when ADX confirms a strong trend. In a range the DI lines cross constantly and those signals fail.
What is the difference between DMI and ADX?
DMI's plus and minus lines tell you the direction of the trend, while ADX tells you how strong that trend is. You use them together — direction from DMI, strength from ADX.
Sources & references
- J. Welles Wilder, New Concepts in Technical Trading Systems (1978)
- Zerodha Varsity — Indicators
Published 7 July 2026. Educational content only — not investment advice.