Concept

Harmonic & Fib Ratio Set

Harmonic & Fib Ratio Set, also known as 0.382, 0.5, 0.618, 0.707, is a Elliott & Harmonics concept. The Library holds 1 implementation, a working definition you can pull into Quant.

parameters of the fib toolset

Top Harmonic & Fib Ratio Set indicator

The top custom implementation, built on the original standard Harmonic & Fib Ratio Set formula.

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Harmonic Pattern Detection

Indicator

What is the Harmonic & Fib Ratio Set?

The Harmonic & Fib Ratio Set is the shared vocabulary of levels behind Fibonacci tools and harmonic patterns: 0.382, 0.5, 0.618, 0.707, 0.786, 0.886, 1.13, 1.272, 1.414, 1.618, 2.0, 2.24, 2.618, 3.14, and 3.618. The core is the golden ratio: 1.618 and its reciprocal 0.618, with most other members chained from them by roots and powers (0.786 is the square root of 0.618 and 0.886 its fourth root; 1.272 is the square root of 1.618 and 2.618 its square; 1.13 is the reciprocal of 0.886). Ratios below 1 grade pullbacks; ratios above 1 project beyond the measured swing.

Not every member is Fibonacci-derived. The 0.5 and 2.0 come from the older halving-and-doubling tradition, 0.707 and 1.414 are built on the square root of 2, 2.24 approximates the square root of 5, and 3.14 approximates pi; harmonic trading literature added these because each pattern, from the Gartley to the Crab, is defined by which ratios its legs must reach. The set matters because it standardizes measurement: a fib retracement or fib extension anchored to the same swing reads the same everywhere, so pattern definitions and potential reversal zones all reference one common grid. None of these levels is a guarantee; they are agreed-upon places to look.

The set accreted over most of a century. H.M. Gartley's 1935 book supplied the founding pattern, retracement-based pattern trading at scale; the modern ratio grid was elaborated much later, with Larry Pesavento's ratio-and-pattern work and Scott Carney's harmonic trading books pinning each named pattern to exact ratios (Carney's Bat popularized the 0.886, credited to Jim Kane, and his Crab the 1.618 extension). Each addition earned its place by giving a pattern's completion point a number.

In use, the grid comes with tolerances and discipline. Harmonic completion points are quoted as exact ratios but traded as small bands around them, and measurement conventions (wick to wick, consistently anchored) matter more than the decimals, since sloppy anchoring moves every level. The same numbers double as the Elliott analyst's measuring tape for wave relationships, which is why the set sits at the junction of the Elliott and harmonic traditions.

How to use the ratio set on a chart

The set is a measuring grid; identification means applying it to swings consistently.

  1. 1Anchor the measured swing at genuine pivots, wick to wick by the common convention, and keep the convention fixed across every measurement.
  2. 2Apply the below-1 members (0.382 through 0.886) to grade pullback depth against the measured leg.
  3. 3Apply the above-1 members (1.13 through 3.618) to project completion points and targets beyond the leg.
  4. 4For harmonic work, use each pattern's defining ratios: the Gartley completing near 0.786 of XA, the Bat near 0.886, the Crab at the 1.618 extension.
  5. 5Trade the levels as small bands with tolerances, not exact ticks, and record which ratio produced each line so zones remain auditable.
  6. 6Weight prices where several independent measurements agree, the confluence that potential reversal zones formalize.

How it's calculated

A fixed set of ratios, most derived from the golden ratio, used to grade retracements and extensions of a measured price leg.

ϕ=1+52=1.618034…\phi = \frac{1 + \sqrt{5}}{2} = 1.618034\ldots
Phi family:0.382=1/ϕ2, 0.618=1/ϕ, 1.618=ϕ, 2.618=ϕ2, 3.618=1+ϕ2\text{Phi family:}\quad 0.382 = 1/\phi^2,\ 0.618 = 1/\phi,\ 1.618 = \phi,\ 2.618 = \phi^2,\ 3.618 = 1 + \phi^2
Square roots of the phi family:0.786=0.618, 0.886=0.786, 1.272=1.618, 1.13=1.272\text{Square roots of the phi family:}\quad 0.786 = \sqrt{0.618},\ 0.886 = \sqrt{0.786},\ 1.272 = \sqrt{1.618},\ 1.13 = \sqrt{1.272}
Non-phi members:0.5=1/2, 0.707=1/2, 1.414=2, 2.0, 2.24=5, 3.14=π (values rounded)\text{Non-phi members:}\quad 0.5 = 1/2,\ 0.707 = 1/\sqrt{2},\ 1.414 = \sqrt{2},\ 2.0,\ 2.24 = \sqrt{5},\ 3.14 = \pi\ \text{(values rounded)}
Measured ratio of a pivot C against the leg from A to B:r=∣PC−PB∣∣PB−PA∣\text{Measured ratio of a pivot } C \text{ against the leg from } A \text{ to } B\text{:}\quad r = \frac{\lvert P_C - P_B \rvert}{\lvert P_B - P_A \rvert}
Grid level at ratio r, drawn from the same leg:Level⁡r=PB−r×(PB−PA)\text{Grid level at ratio } r\text{, drawn from the same leg:}\quad \operatorname{Level}_r = P_B - r \times (P_B - P_A)
phi: golden ratio, 1.6180339...
pi: circle constant, 3.14159...
P_A: price where the measured leg starts
P_B: price where the measured leg ends
P_C: price of the pivot tested against the leg
r: ratio of the second move to the leg (r <= 1 retracement, r > 1 extension)
Level_r: chart price at ratio r

Ratios at or below 1 measure pullbacks inside the leg; ratios above 1 project beyond its start (trend-based extension tools instead use Level_r = P_C + r × (P_B - P_A) from a third pivot).

0.5, 0.707, 1.414, 2.0, 2.24 and 3.14 are not phi-derived; harmonic practice uses them alongside the Fibonacci family.

Each harmonic pattern (Gartley, Bat, Butterfly, Crab) fixes which ratios its B, C and D points must hit, usually within a small tolerance.

How traders use it

  • Grading pullback depth: 0.382, 0.5, 0.618, 0.786, and 0.886 mark progressively deeper retracements, and many playbooks key on specific bands such as the golden pocket around 0.618 to 0.65.
  • Defining harmonic patterns: each pattern is a ratio sequence with tolerances (a Bat completes near the 0.886 retracement of XA, a Crab at the 1.618 extension), so the set functions as the alphabet those definitions are written in.
  • Projecting targets: the above-1 members (1.272, 1.618, 2.0, 2.618, 3.618) extend a completed swing forward to set objectives once a level breaks or a pattern completes.
  • Building confluence: when measurements from different swings land near the same price, the overlapping ratios form a confluence zone that practitioners weight more heavily than any single level.
  • Measuring wave relationships: Elliott practice uses the same grid to relate waves, motive waves extending near 1.618 of wave one and corrective waves commonly retracing 0.382 to 0.618, the measured side of the Elliott guidelines.

Harmonic & Fib Ratio Set vs related concepts

Fib Retracement: The retracement tool applies the below-1 members of the set (0.382 through 0.886) to a single swing to grade pullbacks. The ratio set is the vocabulary; the retracement is one instrument that plays it.

Fib Extension: Extensions apply the above-1 members (1.272, 1.618, 2.618 and beyond) to project targets past a swing. Same grid, opposite side of 1.0.

Golden Pocket: The golden pocket is one narrow slice of the set, the zone around the 0.618 to 0.65 retracement, singled out as a high-interest pullback area. The set is the full menu; the pocket is a single popular order.

Concept family

Elliott & Harmonics

33 concepts mapped · 33 in the Library

Harmonic & Fib Ratio Set FAQ

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