Pattern Detail

Deep Crab

A Crab variant with a deeper 0.886 B point, completing at the same 1.618 extension.

X A B C D
  • B = 0.886 of XA
  • C = 0.382-0.886 of AB
  • D = 2.0-3.618 of BC
  • D = 1.618 of XA
Idealized bullish Deep Crab. It completes at a low and projects a move up.

Bullish Deep Crab

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How to read this

Everything here is in R, the setup's own risk. 1R is the distance from the entry (the pattern's closing price) to where it would be proven wrong — its lowest low over the 4 bars that form it. So "offered 2R" means price ran twice that distance in your favor at some point before the stop. It does not assume you took profit there: a target is a strategy choice.

Room offered (≥ 1R)

50.0%

Too few to trust

Offered at least 1× its risk before the stop, vs 44.1% for a random long entry (+5.9 pts).

Move size vs normal

1.21×

Realized range over the next 20 bars vs a random bar. Precedes a bigger move.

Typical room (20-bar)

1.25R

Average run in favor (capped at 3R), vs 1.16R for a random long entry.

Summary

Offered ≥1R 50.0% of the time vs 44.1% for a random long entry. The 5.9-point gap is no bigger than the ±30.8-point margin of error you would get by chance from 10 occurrences. Not a reliable edge.

Room offered, this setup vs a random long entry

Only 10 occurrences. The breakdown below is shown in full, but a sample this small is anecdotal, a hint, not a measured edge. That is usually a limit of available history, not a flaw in the pattern. For a firmer read, try a lower timeframe or a more active instrument.

Outcome This setup Random entry Edge
Offered ≥ 1R 50.0% 44.1% +5.9
Offered ≥ 2R 20.0% 24.7% -4.7
Offered ≥ 3R 20.0% 15.7% +4.3
Stopped < 1R 50.0% 42.7% +7.3
Went sideways 0.0% 13.2% -13.2

10 occurrences · 10,656 random-entry controls · 20-bar horizon

Bearish Deep Crab

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How to read this

Everything here is in R, the setup's own risk. 1R is the distance from the entry (the pattern's closing price) to where it would be proven wrong — its highest high over the 4 bars that form it. So "offered 2R" means price ran twice that distance in your favor at some point before the stop. It does not assume you took profit there: a target is a strategy choice.

Room offered (≥ 1R)

66.7%

Too few to trust

Offered at least 1× its risk before the stop, vs 43.0% for a random short entry (+23.6 pts).

Move size vs normal

0.98×

Realized range over the next 20 bars vs a random bar. About normal.

Typical room (20-bar)

1.80R

Average run in favor (capped at 3R), vs 1.16R for a random short entry.

Summary

Offered ≥1R 66.7% of the time vs 43.0% for a random short entry. The 23.6-point gap is no bigger than the ±39.6-point margin of error you would get by chance from 6 occurrences. Not a reliable edge.

Room offered, this setup vs a random short entry

Only 6 occurrences. The breakdown below is shown in full, but a sample this small is anecdotal, a hint, not a measured edge. That is usually a limit of available history, not a flaw in the pattern. For a firmer read, try a lower timeframe or a more active instrument.

Outcome This setup Random entry Edge
Offered ≥ 1R 66.7% 43.0% +23.6
Offered ≥ 2R 66.7% 25.9% +40.8
Offered ≥ 3R 33.3% 17.0% +16.3
Stopped < 1R 33.3% 47.1% -13.8
Went sideways 0.0% 9.9% -9.9

6 occurrences · 10,573 random-entry controls · 20-bar horizon

The Deep Crab is a Crab variant with one change: the B point retraces a deep 0.886 of the X-to-A leg instead of the Crab’s shallower 0.382 to 0.618. It is a five-point structure, X to A to B to C to D, defined by Fibonacci ratios between the legs. The signature is the completion: D extends to a 1.618 extension of the whole X-to-A leg, beyond the origin X.

How to spot it

  • A clear X-to-A trend leg, then a deep pullback that runs almost the full length of it.
  • B retraces 0.886 of XA, C retraces 0.382 to 0.886 of AB, and D projects 2.0 to 3.618 of BC.
  • D lands at a 1.618 extension of XA, beyond the origin X. All four ratios hold at once.
  • The structure completes at D, a swing low in an uptrend (a buy) or a swing high in a downtrend (a sell).

The chart above marks the X, A, B, C, D points on a real occurrence, with the ratio of each leg.

Why it matters

A Deep Crab is a bet on exhaustion at a far overshoot. The deep B point means the pullback inside the structure runs almost the full length of the first leg before the extension begins, and the C-to-D leg then projects price well past the prior origin into a measured extension. Because D pushes beyond X, the Deep Crab fades an overstretched move rather than buying a dip, with the same read as the Crab. The deeper retracement is sometimes taken as a sign of a more decisive structure.

That places it among the extension harmonics, alongside the Crab, where the completion sits beyond the origin. The retracement harmonics, the Gartley and Bat, are the opposite case: D stays short of X, so they buy a dip inside the prior move rather than fade a new high or low. The Deep Crab is a counter-trend member of the family, which is also where it is dangerous: fading a violent move that does not stop, and because the deep B sits close to the origin, a shape that looked like a Deep Crab can resolve as a simple trend continuation instead.

The honest question is not whether the shape can be drawn on a chart, it always can after the fact, but whether a completion actually leads anywhere. That is what the data below measures.

Does it actually work?

A pattern is a setup, not a trade, so the question is not “did it win” but “how much room did the move offer before the structure was proven wrong.” The tabs below answer that across five futures markets (Nasdaq, S&P 500, gold, crude oil, natural gas) and seven timeframes from one minute to one day.

For each completion we measure the room price offered in units of the pattern’s own risk, then set it against what a random swing pivot of the same kind would have done. A Deep Crab that turns up from a swing low is judged against ordinary swing lows; one that turns down from a swing high, against ordinary swing highs. When the completion offers more room more often than those random swings, that shows up as a real edge. When it does not, the page says so plainly.

Harmonic structures are rare, so read the sample size in view. On the slower timeframes a Deep Crab completes only single digits of times, or not at all, while the faster timeframes give a larger sample. Thin samples are flagged for you.

How we measured it

  • Entry is the close of the bar that confirms the D point, the earliest a trader could act without hindsight.
  • One unit of risk, 1R, is the distance from that close to D itself, the swing extreme the structure completes at. A move back through D says the pattern has failed.
  • We follow the next 20 bars and record how far price ran in your favor, in multiples of that risk, before D gave way.
  • The comparison is a random swing pivot of the same side, which already sits at a turning point with a tight stop. That keeps it apples-to-apples: the question is whether a Deep Crab swing runs further than an ordinary swing of the same shape, not whether a tight stop flatters the numbers.

What this page does not cover

  • A profit target. Harmonic tradition puts one at a Fibonacci retracement, but where you take profit is a strategy choice, so this measures only the room the structure tends to offer.
  • A trend filter, or confluence with support, resistance, or a higher-timeframe level, which traders normally use to weight a completion.
  • A guarantee. A valid shape on the chart is a setup, not a certainty. What it tends to do next is exactly what the numbers above describe.

FAQ

Do harmonic patterns like the Deep Crab actually work?

Harmonic patterns are described everywhere but rarely tested honestly. This page scores every completed Deep Crab by the room it offered in units of its own risk, measured against random swing pivots of the same kind, and counts a pattern only on the bar its final pivot confirms, so nothing is read in hindsight. The result is a like-for-like comparison rather than the round-number success rates usually quoted for harmonics.

What is the Deep Crab pattern success rate?

There is no single reliable figure, and the often-cited round-number rates rarely specify instrument, timeframe, or test period, and almost never state what target and stop they assume. The Deep Crab is also uncommon, so counts run low. Rather than quote folklore, this page measures how far a completion runs in units of its own risk and whether that beats an ordinary swing of the same shape. The tabs show that comparison across five markets and seven timeframes.

How is the Deep Crab defined here?

It is a five-point XABCD structure where B retraces 0.886 of XA, C retraces 0.382 to 0.886 of AB, D projects 2.0 to 3.618 of BC, and D extends to 1.618 of XA, beyond the origin, all holding at once within a 5% tolerance. Pivots use 3 bars on each side and are confirmed before they count.

Sample Deep Crab Completions (15)

Based on data through Apr 29, 2026

Time Direction Risk (pts) Room offered Result
Jan 2, 2025 Bullish 80.25 3.00R Ran ≥1R
Sep 2, 2021 Bullish 46.75 1.50R Ran ≥1R
Oct 8, 2018 Bullish 40.25 3.00R Ran ≥1R
Jun 22, 2018 Bullish 29 0.78R Stopped
Mar 27, 2018 Bearish 42 3.00R Ran ≥1R
Jan 19, 2016 Bullish 57.5 0.16R Stopped
Dec 22, 2015 Bearish 5.75 3.00R Ran ≥1R
Aug 5, 2014 Bullish 8.5 1.56R Ran ≥1R
May 28, 2014 Bearish 5 2.20R Ran ≥1R
Sep 20, 2011 Bearish 12.5 2.62R Ran ≥1R
Jul 14, 2011 Bullish 17.75 1.13R Ran ≥1R
May 13, 2011 Bullish 6.25 0.68R Stopped
Nov 25, 2010 Bullish 5.75 0.70R Stopped
Aug 5, 2009 Bullish 1 0.00R Stopped
Mar 12, 2008 Bearish 8.5 0.00R Stopped

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