Learn how to read OHLC data

WHY this matters: Raw price lists are overwhelming. OHLC compresses thousands of trades into four numbers that capture the entire battle between buyers and sellers. It's the foundation of every chart pattern, indicator, and trading decision.

HOW it reveals psychology:

• The Open shows where consensus began
• The High reveals maximum buying enthusiasm
• the Low exposes maximum fear/selling pressure
• The Close is the final verdict—what price won the day's tug-of-war

What Each Component Means

• Open (O): The first traded price when the session begins
• High (H): The highest price reached during the entire session
• Low (L): The lowest price reached during the entire session
• Close (C): The last traded price when the session ends

Time-frame flexibility: These four values work for ANY duration—a 5-minute chart has OHLC for each5-minute bar, a daily chart has OHLC for each trading day.

Let's build OHLC from scratch. Imagine a stock trades at these prices during a session: $\text{All trades: } \{100, 102, 101, 105 103, 99, 104, 106 105\}$

Step 1 — Open: By definition, the chronological first trade: $O = \text{first element} = 100$ WHY? Because it establishes the initial equilibrium price where the market opened for business.

Step 2 — Close: By definition, the chronological last trade: $C = \text{last element} = 105$ WHY? Because it's the final price the market agreed upon—the "closing argument" that sets overnight sentiment.

Step 3 — High: The maximum over all trades: $H = \max(\text{all trades}) = 106$ WHY? This marks the point where buying power was strongest—bulls pushed as far as they could go.

Step 4 — Low: The minimum over all trades: $L = \min(\text{all trades}) = 99$ WHY? This marks maximum fear/selling—bears pushed as far as they could go.

The Compression Principle: Instead of storing all 9 trades, we compress to $(O, H, L, C) = (100, 106, 99, 105)$. We've lost granularity but gained interpretability—these four numbers tell us:

• Started at 100 ✓
• Bulls reached 106 ✓
• Bears dragged to 99 ✓
• Closed at 105 (bulls won the day) ✓

Visual Representations

OHLC data is displayed in two main formats:

1. OHLC Bar Chart

Why vertical? The line spans the trading range (H - L), showing volatility. Why horizontal ticks? They show directionality—if right tick (Close) is above left tick (Open), buyers won; if below, sellers won.

2. Candlestick Chart

Body color logic:

• Green/White: Close > Open (bullish, buyers won)
• Red/Black: Close < Open (bearish, sellers won)

WHY candlesticks? They're visually faster to parse—color instantly shows who won, body size shows margin of victory,wick length shows rejected prices.

Derivation of visual priority: $\text{Body height} = |C - O| \quad \text{(magnitude of directional move)}$ $\text{Upper wick} = H - \max(O, C) \quad \text{(rejected highs)}$ $\text{Lower wick} = \min(O, C) - L \quad \text{(rejected lows)}$

Given OHLC: $(98, 105, 97, 104)$

Step-by-step interpretation:

1. Open = 98: Market started trading at₹98

   • Why this matters? Sets the baseline—all price action is relative to this.

2. High = 105: Bulls pushed price to ₹105 at some point

   • Why this matters? Shows ₹105 was tested as resistance. Buyers were willing to pay up to here.

3. Low = 97: Bears pushed price down to ₹97

   • Why this matters? Shows ₹97 was tested as support. Sellers couldn't break below despite trying.

4. Close = 104: Final settlement at ₹104

   • Why this matters? Close > Open (+6 points), so buyers won the day. Close near High (104 vs 105) shows strong conviction—they held most gains.

Visual: Green candlestick body from 98→104, upper wick to 105 (small), lower wick to 97 (longer).

Psychology: Bears tried to take control early (pushed to 97), but bulls overpowered them and closed strong. The small upper wick shows only minor profit-taking at highs.

Given OHLC: $(152, 155, 148, 149)$

Step-by-step:

1. Open = 152: Started at ₹152
2. High = 155: Bulls tried to rally (+3 from open)
   • Key insight: They failed to sustain it (close is way below high).
3. Low = 148: Bears dominated, pushed down -4 from open
4. Close = 149: Settled at ₹149, close < open (−3 points)

Visual: Red candlestick body from 152→149, upper wick to 155, lower wick to 148.

Psychology: Bulls had early optimism (reached 155), but bears reversed the move. Close below open = bearish day. However, close > low (149 vs 148) shows buyers defended the ₹148 level at day's end—partial recovery.

Given OHLC: $(200, 203, 198, 200.5)$

Analysis:

• Open ≈ Close (200 vs 200.5, only₹0.50 difference)
• High = 203 (+3), Low = 198 (−2)

Visual: Tiny body (almost a line), long upper and lower wicks.

Psychology: A doji signals indecision. Bulls pushed to 203, bears pushed to 198, but neither side could hold ground—they cancelled each other out. Often appears at trend turning points or consolidation zones.

Extracting Information: The Trading Range

The trading range measures volatility: $\text{Range} = H - L$

WHY it matters:

• Large range (e.g., 20 points): High volatility, strong emotions, big moves
• Small range (e.g., 2 points): Low volatility, boredom, consolidation

Close Position Ratio (where did we finish within the range?): $\text{CPR} = \frac{C - L}{H - L}$

• CPR near 1.0: Closed at top of range (bullish strength)
• CPR near 0.0: Closed at bottom of range (bearish weakness)
• CPR ≈ 0.5: Closed middle of range (neutral)

Example: If H=110, L=100, C=108: $\text{CPR} = \frac{108 - 100}{110 - 100} = \frac{8}{10} = 0.8$ Interpretation: Closed in top 20% of range—strong bullish day even if open was higher.

OHLC: $(50, 58, 49, 55)$

Range: $58 - 49 = 9$ points (decent volatility)

Directional move: $C - O = 55 - 50 = +5$ points (bullish)

CPR: $\frac{55 - 49}{58 - 49} = \frac{6}{9} = 0.667$

Interpretation: While close > open (bullish), the CPR of 0.67 means we closed only 2/3 up the range. The stock reached58 (high) but couldn't hold—some profit-taking occurred. Moderate bullish conviction, not extreme.

Common Patterns in OHLC

Body vs. Wick Analysis

WHY this matters:

• High ratio (>0.7): Marubozu pattern—strong directional move, little indecision
• Low ratio (<0.3): Spinning top/doji—indecision, wicks dominate

Example:

• OHLC = $(100, 110, 99, 109)$: Body = 9, Range = 11, Ratio = 0.82→ Strong trend
• OHLC = $(100, 105, 98, 101)$: Body = 1, Range = 7, Ratio = 0.14 → Indecision

Upper/Lower Wick Significance

Upper wick = rejection of higher prices: $\text{Upper wick} = H - \max(O, C)$

Lower wick = rejection of lower prices: $\text{Lower wick} = \min(O, C) - L$

Long upper wick: Bears rejected the rally (bearish signal)
Long lower wick: Bulls rejected the selloff (bullish signal)
Both long: Extreme volatility, tug-of-war, no winner

Wrong thinking: "Close > Open, so it's bullish—I should buy!"

Why it feels right: Green candles look good, simple rule.

The fix: You MUST know WHERE the close is relative to high/low AND the prior price action.

Counter-example:

• Stock at₹200 yesterday
• Today's OHLC = $(180, 185, 175, 182)$
• Close > Open (182 > 180) = green candle ✓
• BUT: Stock gapped down from 200→180, and despite the green candle, it's down₹18 from yesterday!

Correct interpretation: This is a bearish continuation with a weak bounce, not a bullish reversal. The open itself was a collapse.

Steel-man the mistake: Focusing only on O vs C makes candlestick reading easy and visual. But price exists in a continuum—each bar connects to the prior bar's story. Context defeats isolated pattern-matching.

Wrong thinking: "Longwick = reversal signal"

Why it feels right: Wicks show rejection, rejection means reversal.

The fix: Wick significance depends on WHICH boundary was tested.

Example:

• Uptrend: Long lower wick = buyers defendedip (bullish continuation)
• Downtrend: Long lower wick = dead cat bounce, still bearish

Steel-man: Wicks DO show rejection, which is real. But rejection of an attempt to go higher (upper wick) has opposite meaning to rejection of an attempt to go lower (lower wick). Direction matters.

"Octopus Hugs Little Clownfish"

• Octopus = Open (starts the story)
• Hugs = High (peak of affection/buying)
• Litle = Low (small, bottom point)
• Clownfish = Close (colorful finish, tells you the mood)

Or: "Only Happy Losers Close" → in a red candle, the "loser" (bears) make you close lower!

Open = the price of your first cup sold (₹10)
High = the most someone paid all hour (one customer really wanted it, paid ₹15!)
Low = the cheapest you sold it for (it was hot, you dropped to ₹8to clear inventory)
Close = the last cup's price (₹12)

So OHLC = (10, 15, 8, 12). Looking at this, what happened? You started at₹10, someone paid as high as ₹15 (awesome!), but you also had to go as low as ₹8 (oof), and you ended at ₹12. Since close (₹12) > open (₹10), you had a good hour overall—you raised prices from start to finish!

That's exactly how stock traders look at each hour/day of trading. Those four numbers tell the whole emotional story.

Connections

• 3.1.01-Understanding-Price-Charts — OHLC is how we plot every point on price charts
• 3.1.03-Candlestick-Patterns — These patterns are built from OHLC relationships
• 3.2.01-Support-and-Resistance — High/Low become future support/resistance zones
• 3.3.01-Trend-Identification — Series of higher closes/opens define uptrends
• 4.1.02-MovingAverages — Calculated from close prices (OHLC's most important value)
• 5.1.01-Volume-Analysis — Volume confirms whether OHLC moves are genuine
• 3.1.04-Gap-Analysis — Gaps occur when today's open ≠ yesterday's close

Flashcards

What are the four components of OHLC data? :: Open (first price), High (maximum price), Low (minimum price), Close (last price) for a given time period.

Concept Map

Hinglish (regional understanding)