📖William Gann

Square of Nine

🌳 Advanced★★★★☆

Square of Nine reveals natural support and resistance levels. Gann used this tool to calculate price targets with remarkable accuracy Use the Square of Nine calculator to find support/resistance at 90, 180, 270, 360 degrees The spiral arrangement of numbers reveals natural price harmonics Key insight: The Square of Nine arranges numbers in a spiral pattern from center outward, with geometric relationships revealing price targets. Start with a minimal checklist: Am I trading too much?; Is this a high-probability setup?; Would I be better off waiting?.

  • Am I trading too much?
  • Is this a high-probability setup?
  • Would I be better off waiting?
  • Be selective about trades

Avoid misuse: Confusing a low price with true cheapness

💬

The Square of Nine arranges numbers in a spiral pattern, revealing price levels of support and resistance. Key angles on the square indicate where prices are likely to reverse.

— The W.D. Gann Master Commodities Course，1951

🏠 Everyday Analogy

Imagine a spiral staircase drawn on graph paper, each step marked with a number. Some steps line up perfectly with windows, doors and corners of the building. When you walk to those aligned steps, light or obstacles often appear. The Square of Nine is like that staircase for prices and time: when prices reach certain aligned steps (angles), markets often meet invisible walls or doors and change pace or direction.

📖 Core Interpretation

The spiral arrangement of numbers reveals natural price harmonics
💎 Key Insight：The Square of Nine arranges numbers in a spiral pattern from center outward, with geometric relationships revealing price targets. Numbers on the same angle from center act as support/resistance. This tool combines price, time, and geometry to forecast market turns. Traders use it to identify where prices are likely to pause or reverse based on mathematical harmony.

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❓ Why It Matters

Gann used this tool to calculate price targets with remarkable accuracy

🎯 How to Practice

Use the Square of Nine calculator to find support/resistance at 90, 180, 270, 360 degrees

🎙️ Master's Voice

Do not overtrade. Less trading leads to better results.
Gann warned against excessive trading. Each trade carries costs and risks. The best traders are selective, waiting for high-probability setups rather than trading constantly.

⚔️ Practical Guide

✅ Decision Checklist

  • Am I trading too much?
  • Is this a high-probability setup?
  • Would I be better off waiting?

📋 Action Steps

  1. Be selective about trades
  2. Wait for high-probability setups
  3. Track trading frequency and results

🚨 Warning Signs

  • Overtrading
  • Taking marginal setups
  • Trading for action rather than profit

⚠️ Common Pitfalls

✕Confusing a low price with true cheapness
✕Using one metric without business context
✕Overly optimistic assumptions that erase margin of safety

📚 Case Studies

1
Pre-Crash Market Timing (1929)
A trader used Gann’s Square of Nine to anticipate time and price resistance in the Dow as it approached 380, identifying a major top near key square levels before the 1929 crash.
✨ Outcome：Reduced long exposure and shorted selectively, preserving capital during the crash.
2
Black Monday Crash Setup (1987)
An analyst applied the Square of Nine to the S&P 500, noting geometric resistance and time cycles converging in late summer 1987, warning of a sharp correction before Black Monday.
✨ Outcome：Exited index positions in advance and re-entered gradually after the crash at lower prices.

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