AB=CD

What this pattern measures

AB=CD is the simplest harmonic structure and the building block the others are made from. It is four points: a leg from A to B, a partial retracement from B to C, then a final leg from C to D that is equal in length to the A-to-B leg. Because it only needs two equal legs around a retracement, it is the most common pattern in the family.

This page measures what happened after each completed AB=CD, scored by the trade the structure implies: enter at the point of equality, target a 0.618 retracement of the move, stop just beyond the completion.

Definitions used on this page:

• B to C retraces 0.618 to 0.786 of AB, and C to D matches AB in length.
• Pivots are confirmed swing highs and lows at balanced strictness: 3 bars on each side, with a 5% tolerance on every ratio. A pattern is counted only on the bar its final pivot confirms.
• The implied trade enters at the close of the confirming bar, targets a 0.618 retracement of the structure, and stops just beyond D. It is given 60 bars to resolve before timing out.
• Outcomes are measured on CME:NQ at 15-minute and 5-minute bars.

Why it matters

The idea is symmetry. If the market moved a certain distance from A to B, paused, and then resumed, the second leg often travels a similar distance before stalling. D is the point of equality, where the move has covered the same ground twice and is read as complete. The simplicity that makes it common also makes it noisy: two equal legs happen all the time without marking anything significant, so without context the AB=CD fires on a lot of meaningless structure. That frequency is what makes it useful for seeing how a high-volume setup behaves over a long sample.

How to read the numbers

• Win rate is the share of decided trades, wins plus losses, that reached the target before the stop. Timeouts are excluded and reported on their own.
• Avg return is the mean outcome across every completed pattern, signed so positive favours the trade direction.
• Avg win and avg loss split the decided trades into their winning and losing sides.
• Bullish and bearish counts show which direction the structure completed in.

What’s not here

• No context filter, which a high-frequency structure like this needs most.
• No confluence with longer-term levels at the point of equality.
• A single contract and two intraday timeframes.