Candlestick Pattern Recognition

TechKit implements 61 Japanese candlestick patterns, 100% compatible with TA-Lib.

Pattern Output Values

Value	Meaning
+100	Bullish pattern detected
-100	Bearish pattern detected
+200	Strong bullish pattern
-200	Strong bearish pattern
0	No pattern detected

API Usage

Python

from techkit import talib_compat as ta
import numpy as np

# Single pattern detection
hammer = ta.CDLHAMMER(open, high, low, close)

# Check for pattern
if hammer[-1] != 0:
    print(f"Hammer detected: {hammer[-1]}")

# Scan multiple patterns
patterns = {
    'hammer': ta.CDLHAMMER(open, high, low, close),
    'engulfing': ta.CDLENGULFING(open, high, low, close),
    'doji': ta.CDLDOJI(open, high, low, close),
}

Node.js

const tk = require('techkit');

// Single pattern
const hammer = tk.CDLHAMMER(open, high, low, close);

// Batch scan all patterns
const results = tk.scanAllPatterns(open, high, low, close);

C

tk_indicator pat = tk_cdl_hammer_new();
for (int i = 0; i < n; i++) {
    tk_ohlcv bar = {open[i], high[i], low[i], close[i], volume[i]};
    tk_result r = tk_update_ohlcv(pat, &bar);
    if (r.valid && r.value != 0) {
        printf("Hammer at bar %d: %.0f\n", i, r.value);
    }
}
tk_free(pat);

Pattern Categories

Single Candle Patterns

Patterns formed by analyzing a single candlestick.

CDLDOJI - Doji

A Doji forms when open and close are virtually equal, indicating market indecision.

Visual Pattern

    │       Long upper shadow (optional)
    │
────┼────   Open ≈ Close (very small body)
    │
    │       Long lower shadow (optional)

Detection Rules

Body size is less than a small percentage of the total range
|close - open| < threshold × (high - low)

Characteristics

Property	Value
Input	OHLC
Lookback	0
Output	0, +100, or -100

Trading Usage

Indecision: Neither buyers nor sellers in control
Reversal potential: More significant at trend extremes
Confirmation needed: Wait for next candle to confirm direction

CDLDOJISTAR - Doji Star

A Doji that gaps away from the previous candle.

Visual Pattern

Bullish:          Bearish:
    ■                 █
    ■                 █
    ■                 █
                      
    ─┼─           ─┼─

Detection Rules

Previous candle has substantial body
Current candle is a Doji
Gap between bodies (Doji gaps away from previous close)

Trading Usage

Bullish Doji Star: After downtrend, gaps down = potential reversal up
Bearish Doji Star: After uptrend, gaps up = potential reversal down

CDLDRAGONFLYDOJI - Dragonfly Doji

Doji with long lower shadow and no/minimal upper shadow.

Visual Pattern

────┬────   Open = Close = High
    │
    │       Long lower shadow
    │
    │
    ▼

Detection Rules

Open ≈ Close ≈ High
Long lower shadow (> 2× body size)
No or minimal upper shadow

Trading Usage

Bullish: After downtrend, shows rejection of lower prices
Support: Lower shadow tested and rejected

CDLGRAVESTONEDOJI - Gravestone Doji

Doji with long upper shadow and no/minimal lower shadow.

Visual Pattern

    ▲
    │
    │       Long upper shadow
    │
    │
────┴────   Open = Close = Low

Detection Rules

Open ≈ Close ≈ Low
Long upper shadow (> 2× body size)
No or minimal lower shadow

Trading Usage

Bearish: After uptrend, shows rejection of higher prices
Resistance: Upper shadow tested and rejected

CDLLONGLEGGEDDOJI - Long-Legged Doji

Doji with long shadows on both sides.

Visual Pattern

    │
    │       Long upper shadow
    │
────┼────   Open ≈ Close
    │
    │       Long lower shadow
    │

Trading Usage

High indecision: Both buyers and sellers active
Volatile: Large price range but no net movement

CDLRICKSHAWMAN - Rickshaw Man

Similar to Long-Legged Doji with body at center of range.

Detection Rules

Doji pattern
Open/Close near the midpoint of high-low range
Long shadows on both sides

CDLHAMMER - Hammer

Bullish reversal pattern with small body at top and long lower shadow.

Visual Pattern

    ┌─┐     Small body at top
    │█│
    └┬┘
     │
     │      Long lower shadow (≥ 2× body)
     │
     ▼

Detection Rules

Small real body at upper end of trading range
Lower shadow at least 2× the body length
Little or no upper shadow
Appears after downtrend

Trading Usage

Bullish reversal: Shows rejection of lower prices
Confirmation: Wait for bullish candle next day
Stop loss: Below hammer low

CDLHANGINGMAN - Hanging Man

Same shape as Hammer but appears after uptrend (bearish).

Visual Pattern

Same as Hammer.

Detection Rules

Same shape as Hammer
Appears after uptrend (not downtrend)

Trading Usage

Bearish warning: Potential top formation
Confirmation critical: Needs bearish follow-through

CDLINVERTEDHAMMER - Inverted Hammer

Bullish reversal with small body at bottom and long upper shadow.

Visual Pattern

     ▲
     │
     │      Long upper shadow (≥ 2× body)
     │
    ┌┴┐
    │█│     Small body at bottom
    └─┘

Detection Rules

Small real body at lower end of range
Long upper shadow (≥ 2× body)
Little or no lower shadow
Appears after downtrend

Trading Usage

Bullish reversal potential: But needs confirmation
Less reliable: Than standard Hammer

CDLSHOOTINGSTAR - Shooting Star

Same shape as Inverted Hammer but after uptrend (bearish).

Visual Pattern

Same as Inverted Hammer.

Detection Rules

Same shape as Inverted Hammer
Appears after uptrend

Trading Usage

Bearish reversal: Shows rejection of higher prices
More reliable: With gap up before pattern

CDLMARUBOZU - Marubozu

Full body candle with no shadows.

Visual Pattern

Bullish:    Bearish:
┌───┐       ┌───┐
│   │       │███│
│   │       │███│
│   │       │███│
└───┘       └───┘
O=L,C=H     O=H,C=L

Detection Rules

No upper shadow (open or close = high)
No lower shadow (open or close = low)

Trading Usage

Strong conviction: Buyers (white) or sellers (black) dominated
Continuation: Often indicates strong trend

CDLLONGLINE - Long Line Candle

Candle with unusually long body.

Detection Rules

Body length > average body length × threshold

Trading Usage

Strong momentum in direction of the candle

CDLSHORTLINE - Short Line Candle

Candle with unusually short body.

Detection Rules

Body length < average body length × threshold

Trading Usage

Weak momentum, potential pause or reversal

CDLSPINNINGTOP - Spinning Top

Small body with shadows on both sides.

Visual Pattern

    │
    ┌┴┐
    │█│     Small body
    └┬┘
    │

Detection Rules

Small real body
Upper and lower shadows present
Not a Doji (has visible body)

Trading Usage

Indecision: Similar to Doji but with small body
Consolidation: Market taking a breather

CDLHIGHWAVE - High Wave Candle

Small body with very long shadows on both sides.

Detection Rules

Small real body
Very long upper AND lower shadows
Shadows significantly longer than typical

Trading Usage

Extreme indecision: Large volatility, no resolution
Reversal potential: At trend extremes

CDLTAKURI - Takuri (Dragonfly Doji with longer shadow)

Dragonfly Doji variant with very long lower shadow.

Detection Rules

Doji or near-Doji body
Very long lower shadow (> 3× typical)
No or minimal upper shadow

Trading Usage

Strong bullish signal: When appearing after downtrend
Extreme rejection: Of lower prices

Two Candle Patterns

Patterns formed by analyzing two consecutive candlesticks.

CDLENGULFING - Engulfing Pattern

Strong reversal pattern where second candle completely engulfs the first.

Visual Pattern

Bullish Engulfing:        Bearish Engulfing:
   │                           ▲
   ■     Day 1 (bearish)       │
   ■                           █     Day 2 (bearish)
   │                           █
                               █
   ▲                           █
   │                           │
   █     Day 2 (bullish)
   █                           ■     Day 1 (bullish)
   █                           ■
   │                           │

Detection Rules (Bullish)

Downtrend in progress
First candle: bearish (black/red body)
Second candle: bullish (white/green body)
Second body opens below first body’s low
Second body closes above first body’s high

Characteristics

Property	Value
Lookback	1
Output	+100 (bullish), -100 (bearish)

Trading Usage

Bullish Engulfing: Strong reversal at bottom, high reliability
Bearish Engulfing: Strong reversal at top
Volume: Higher volume on engulfing candle increases reliability
Entry: On close of engulfing candle or next open
Stop: Below/above engulfing candle’s extreme

CDLHARAMI - Harami Pattern

Second candle’s body contained within first candle’s body.

Visual Pattern

Bullish Harami:           Bearish Harami:
   │                           ▲
   ■                           │
   ■                           █
   ■─┬─                        █─┬─
   ■ │█│                       █ │■│
   ■─┴─                        █─┴─
   │                           │

Detection Rules

First candle: long body
Second candle: small body contained within first body
Opposite colors (classic) or same color (less reliable)

Trading Usage

Reversal warning: Less reliable than Engulfing
Confirmation needed: Wait for third candle
“Pregnant” pattern: Japanese term harami means pregnant

CDLHARAMICROSS - Harami Cross

Harami where second candle is a Doji.

Detection Rules

First candle: long body
Second candle: Doji contained within first body

Trading Usage

Stronger than regular Harami: Doji adds indecision signal
More reliable reversal indication

CDLPIERCING - Piercing Pattern

Bullish reversal - second candle closes above midpoint of first.

Visual Pattern

   │
   ■     Day 1 (bearish)
   ■
   ■
   ■──── Midpoint
   │
   
   │
   █     Day 2 opens below Day 1 low
   █     closes above Day 1 midpoint
   █
   ▲

Detection Rules

Downtrend in progress
First candle: long bearish body
Second candle: opens below first’s low
Second candle: closes above midpoint of first’s body
Second candle: does not close above first’s open

Trading Usage

Bullish reversal: At support levels
Less strong than Engulfing: Doesn’t fully engulf

CDLDARKCLOUDCOVER - Dark Cloud Cover

Bearish reversal - opposite of Piercing Pattern.

Detection Rules

Uptrend in progress
First candle: long bullish body
Second candle: opens above first’s high
Second candle: closes below midpoint of first’s body
Second candle: does not close below first’s open

Trading Usage

Bearish reversal: At resistance levels

CDLBELTHOLD - Belt Hold

Long candle that opens at extreme and closes opposite.

Visual Pattern

Bullish Belt Hold:    Bearish Belt Hold:
   ▲                       │
   │                       ■ Opens at high
   █                       ■
   █                       ■
   █                       ■ Closes near low
   │ Opens at low          ▼

Detection Rules

Bullish:

Opens at or near the low
Closes significantly higher
Little or no lower shadow

Bearish: Opposite

CDLCOUNTERATTACK - Counterattack Lines

Two opposite-colored candles with same close.

Detection Rules

First candle: in direction of trend
Second candle: opposite color
Both candles close at same price level

CDLHIKKAKE - Hikkake Pattern

Inside bar breakout failure pattern.

Detection Rules

Inside bar (bar 2 within bar 1)
Breakout in one direction (bar 3)
Reversal back through inside bar (bar 4-5)

CDLHIKKAKEMOD - Modified Hikkake

Variation of Hikkake with additional confirmation.

CDLHOMINGPIGEON - Homing Pigeon

Bullish pattern similar to Harami but both candles bearish.

Detection Rules

First candle: long bearish body
Second candle: smaller bearish body contained within first

CDLINNECK - In Neck Pattern

Weak continuation pattern after downtrend.

Detection Rules

Downtrend
First candle: long bearish
Second candle: opens with gap down, closes at or just below first’s close

CDLONNECK - On Neck Pattern

Similar to In Neck but closes at first’s low.

CDLKICKING - Kicking Pattern

Strong reversal with two Marubozu candles of opposite color with gap.

Visual Pattern

Bullish:              Bearish:
┌───┐                 ┌───┐
│███│ Day 1          │   │ Day 1
│███│ (bearish)       │   │ (bullish)
└───┘                 └───┘
  ↑gap                  ↓gap
┌───┐                 ┌───┐
│   │ Day 2          │███│ Day 2
│   │ (bullish)       │███│ (bearish)
└───┘                 └───┘

Detection Rules

First candle: Marubozu (no shadows)
Gap in opposite direction
Second candle: Marubozu opposite color

Trading Usage

Very strong signal: Two opposing Marubozus
Rare pattern: High reliability when occurs

CDLKICKINGBYLENGTH - Kicking by Length

Kicking pattern determined by candle length comparison.

CDLMATCHINGLOW - Matching Low

Two candles with same low - support confirmation.

Detection Rules

Two bearish candles
Both close at same price level

CDLTHRUSTING - Thrusting Pattern

Weak bullish pattern - closes into prior body but below midpoint.

Detection Rules

Downtrend
First candle: bearish
Second candle: opens below first’s low
Second candle: closes within first’s body but below midpoint

CDL2CROWS - Two Crows

Bearish continuation after uptrend.

Detection Rules

Uptrend with long bullish first candle
Second candle: bearish, gaps up, closes within first’s body
Third candle: bearish, opens within second, closes within first

Three or More Candle Patterns

Patterns formed by analyzing three or more consecutive candlesticks.

CDLMORNINGSTAR - Morning Star

Strong bullish reversal pattern.

Visual Pattern

Day 1:        Day 2:        Day 3:
   │                           ▲
   ■                           │
   ■                           █
   ■                           █
   ■          ─┼─              █
   │           │               │

Detection Rules

Downtrend in progress
First candle: long bearish body
Second candle: small body (star), gaps down from first
Third candle: long bullish body, closes above midpoint of first

Characteristics

Property	Value
Lookback	2
Output	+100

Trading Usage

Strong bullish reversal: One of the most reliable patterns
Star gaps important: Larger gap = stronger signal
Entry: On close of third candle
Stop: Below low of the star (second candle)

CDLEVENINGSTAR - Evening Star

Strong bearish reversal pattern (opposite of Morning Star).

Visual Pattern

Day 1:        Day 2:        Day 3:
   ▲           │               │
   │          ─┼─              ■
   █                           ■
   █                           ■
   █                           ■
   │                           │

Detection Rules

Uptrend in progress
First candle: long bullish body
Second candle: small body (star), gaps up from first
Third candle: long bearish body, closes below midpoint of first

Trading Usage

Strong bearish reversal: High reliability

CDLMORNINGDOJISTAR - Morning Doji Star

Morning Star where middle candle is a Doji.

Trading Usage

Stronger than regular Morning Star: Doji adds emphasis

CDLEVENINGDOJISTAR - Evening Doji Star

Evening Star where middle candle is a Doji.

CDL3WHITESOLDIERS - Three White Soldiers

Three consecutive long bullish candles.

Visual Pattern

Detection Rules

Three consecutive bullish candles
Each opens within prior body
Each closes at or near its high
Each has a long body

Trading Usage

Strong bullish continuation/reversal: Very reliable
Volume confirmation: Higher volume strengthens signal

CDL3BLACKCROWS - Three Black Crows

Three consecutive long bearish candles (opposite of 3 White Soldiers).

Detection Rules

Three consecutive bearish candles
Each opens within prior body
Each closes at or near its low
Each has a long body

Trading Usage

Strong bearish continuation/reversal: Very reliable

CDL3INSIDE - Three Inside Up/Down

Harami followed by confirmation candle.

Detection Rules (Three Inside Up)

First two candles form bullish Harami
Third candle closes above first candle’s open

CDL3OUTSIDE - Three Outside Up/Down

Engulfing followed by confirmation candle.

Detection Rules (Three Outside Up)

First two candles form bullish Engulfing
Third candle closes above second candle’s close

CDL3LINESTRIKE - Three Line Strike

Three soldiers/crows followed by opposite Engulfing.

Detection Rules

Three White Soldiers (or Three Black Crows)
Fourth candle engulfs all three in opposite direction

Trading Usage

Continuation despite appearance: Usually continues original trend
Counterintuitive: Looks like reversal but often isn’t

CDL3STARSINSOUTH - Three Stars in the South

Bullish reversal showing decreasing selling pressure.

Detection Rules

Three bearish candles
Each has progressively shorter body
Each has progressively shorter lower shadow
Shows diminishing bearish momentum

CDLABANDONEDBABY - Abandoned Baby

Extreme reversal with island gaps.

Detection Rules

First candle: in trend direction
Second candle: Doji that gaps away (island)
Third candle: opposite direction, gaps past Doji

Trading Usage

Very strong reversal: Gap isolation makes it rare and reliable
Rare pattern: Not common but high reliability

CDLADVANCEBLOCK - Advance Block

Weakening of Three White Soldiers pattern.

Detection Rules

Three bullish candles
Second and third have progressively smaller bodies
Long upper shadows on second and/or third

Trading Usage

Weakening uptrend: Bullish momentum fading

CDLBREAKAWAY - Breakaway Pattern

Gap followed by trend, then gap back.

CDLCONCEALBABYSWALL - Concealing Baby Swallow

Rare bullish pattern with two Marubozus.

CDLGAPSIDESIDEWHITE - Up/Down Gap Side-by-Side White Lines

Gap followed by two similar white candles.

CDLIDENTICAL3CROWS - Identical Three Crows

Three Black Crows where each opens at prior close.

CDLLADDERBOTTOM - Ladder Bottom

Five-candle bullish reversal pattern.

CDLMATHOLD - Mat Hold

Five-candle continuation pattern.

CDLRISEFALL3METHODS - Rising/Falling Three Methods

Continuation pattern with consolidation.

Detection Rules (Rising)

First candle: long bullish
Next 2-4 candles: small bearish, stay within first’s range
Final candle: long bullish, closes above first’s close

Trading Usage

Strong continuation: Pause in uptrend then resumption

CDLSEPARATINGLINES - Separating Lines

Opposing candles with same open.

CDLSTALLEDPATTERN - Stalled Pattern

Bullish trend stalling.

CDLSTICKSANDWICH - Stick Sandwich

Two similar bearish candles with bullish between.

CDLTASUKIGAP - Tasuki Gap

Continuation pattern with partial gap fill.

CDLTRISTAR - Tri-Star

Three consecutive Dojis.

Detection Rules

Three consecutive Dojis
Middle Doji gaps from first
Third Doji gaps from second (opposite direction)

Trading Usage

Very rare: Extreme indecision
Strong reversal potential: When it occurs

CDLUNIQUE3RIVER - Unique Three River Bottom

Rare bullish reversal pattern.

CDLUPSIDEGAP2CROWS - Upside Gap Two Crows

Bearish pattern with gap and two crows.

CDLXSIDEGAP3METHODS - Upside/Downside Gap Three Methods

Gap continuation pattern.

Pattern Summary Table

Pattern	Candles	Type	Signal
CDLDOJI	1	Neutral	Indecision
CDLHAMMER	1	Bullish	Reversal
CDLSHOOTINGSTAR	1	Bearish	Reversal
CDLENGULFING	2	Both	Strong Reversal
CDLHARAMI	2	Both	Reversal Warning
CDLPIERCING	2	Bullish	Reversal
CDLDARKCLOUDCOVER	2	Bearish	Reversal
CDLMORNINGSTAR	3	Bullish	Strong Reversal
CDLEVENINGSTAR	3	Bearish	Strong Reversal
CDL3WHITESOLDIERS	3	Bullish	Continuation/Reversal
CDL3BLACKCROWS	3	Bearish	Continuation/Reversal
CDL3INSIDE	3	Both	Reversal
CDL3OUTSIDE	3	Both	Reversal
CDL3LINESTRIKE	4	Both	Continuation
CDLABANDONEDBABY	3	Both	Strong Reversal
CDLADVANCEBLOCK	3	Bearish	Weakening
CDLRISEFALL3METHODS	5	Both	Continuation
CDLTRISTAR	3	Both	Reversal

Pattern Scanning

Batch Scanning All Patterns

For efficient pattern detection across all 61 patterns:

Python

from techkit import talib_compat as ta

# Define all pattern functions
PATTERNS = [
    ('CDL2CROWS', ta.CDL2CROWS),
    ('CDL3BLACKCROWS', ta.CDL3BLACKCROWS),
    ('CDL3INSIDE', ta.CDL3INSIDE),
    # ... all 61 patterns
]

def scan_all_patterns(open, high, low, close):
    results = {}
    for name, func in PATTERNS:
        pattern = func(open, high, low, close)
        # Find non-zero values
        signals = [(i, v) for i, v in enumerate(pattern) if v != 0]
        if signals:
            results[name] = signals
    return results

# Usage
detected = scan_all_patterns(open, high, low, close)
for pattern, signals in detected.items():
    print(f"{pattern}: {len(signals)} occurrences")

Node.js

const tk = require('techkit');

// Batch scan
const results = tk.scanAllPatterns(open, high, low, close);
console.log(results);