Composite & famousGator Oscillator
A companion to the Alligator that shows when the trend is sleeping and when it is feeding.
Works in most conditionsEngine-computed on a fixed sample series
What it is
The Gator Oscillator is a companion to Bill Williams' Alligator indicator that turns the three Alligator lines into two simple bar charts so you can see, at a glance, whether a trend is asleep or awake. The Alligator itself is three smoothed averages of different lengths — the Jaw, the Teeth, and the Lips — and Williams described the market as a sleeping alligator when those lines are tangled together and a feeding one when they spread apart. The Gator measures exactly how far apart those lines are and plots it as two histograms, one above a zero line and one below. It answers a single, useful question: is the market currently ranging and directionless, or is it fanning out into a genuine trend, and is that condition strengthening or fading? Because it only summarises the Alligator's geometry, it is best thought of as a phase gauge — a way to read the market's rhythm — rather than a standalone buy-or-sell tool.
How it is calculated
First you need the Alligator's three lines, each a smoothed moving average of the median price (high plus low, divided by two) and each shifted forward in time: the Jaw is a 13-period smoothed average pushed 8 bars into the future, the Teeth an 8-period average pushed 5 bars, and the Lips a 5-period average pushed 3 bars. The Gator's upper histogram is the absolute distance between the Jaw and the Teeth, plotted as positive bars above zero, and the lower histogram is the absolute distance between the Teeth and the Lips, plotted as negative bars below zero. Taking absolute values means both histograms measure only the size of the gaps, not their direction, so the tool describes convergence and divergence rather than up or down. Each bar is then coloured by comparison with the bar before it: green when the current bar is larger than the previous one (the gap is widening) and red when it is smaller (the gap is narrowing). The result is a mirror-image pair of expanding and contracting bars that visualise how the Alligator's mouth is opening or closing.
Reading it, step by step
Read the two histograms together as a picture of the Alligator's mouth. When both bars are small and shrinking, the three lines are intertwined and the market is sleeping — a range with no trend to trade. When both bars grow, the lines are fanning apart and the Alligator is eating — a trend is underway. Colour refines the read: green bars mean the gap on that side is still widening, red that it is narrowing, so two green bars signal a strengthening trend and two red bars a fading one. Bill Williams described four phases in sequence: sleeping (both bars red and small), awakening (one green, one red, as the lines begin to separate), eating (both green, the trend in full flow), and sated or full (both red again after eating, warning the trend is losing appetite). The transition from awakening to eating is the signal that a tradable trend has taken hold, while the shift to the sated phase warns it may be ending.
Best timeframes and settings
The Gator inherits the Alligator's default lengths (13, 8, and 5) with their forward shifts of 8, 5, and 3, and these are rarely changed because Williams' system is meant to be used as designed. It works across timeframes but is most coherent on the charts where the underlying trend structure is clear — 1-hour, 4-hour, and daily for swing trading, though intraday scalpers apply it on shorter bars. Because the smoothing and the forward displacement are baked in, there is limited responsiveness-versus-noise tuning to do; shortening the averages would make the histograms flicker between phases and defeat the tool's purpose. The main practical choice is timeframe rather than parameters: a higher timeframe gives fewer but more reliable phase transitions, a lower one gives more signals with more false starts. Keep the defaults unless you have a specific, tested reason to deviate, since the phase logic depends on the classic proportions of the three lines.
When and where to use it
Use the Gator as a regime and timing overlay to tell trending conditions from ranging ones, so you know when to deploy trend strategies and when to sit on your hands. It is well suited to trending, liquid markets and to any workflow already built around Bill Williams' toolkit, where it pairs with the Alligator, the Awesome Oscillator, and the Accelerator Oscillator. It genuinely helps you avoid the classic error of trading breakouts while the market is asleep, because the sleeping phase is unmistakable. Do not use it as a direction signal — the histograms are unsigned and say nothing about up versus down — and be cautious in persistently choppy markets where the phases flip repeatedly. Treat it as context that gates your other tools rather than as a trigger in its own right.
Strategies that use it
Phase-gated trend entry: wait until the Gator moves from the awakening into the eating phase with both histograms green, then enter in the direction the Alligator's lines are pointing (Lips above Teeth above Jaw for longs), using the Lips or Teeth as a trailing stop. Sleep-avoidance filter: overlay the Gator on any breakout system and simply refuse to take breakout trades while both bars are small and red, only acting once expansion begins, which filters out a large share of false breaks in ranges. Exhaustion-exit strategy: while riding a trend, treat the shift into the sated phase — both bars turning red after a run of green — as a cue to tighten stops or scale out, since it signals the Alligator's mouth is starting to close. Each of these uses the Gator for timing and context and relies on the Alligator's line order or another tool for actual direction.
Combining it with other indicators
The Gator is designed to work with the Alligator, which supplies the direction the Gator's phase read is missing, so the two are almost always used together. The Awesome Oscillator and Accelerator Oscillator, also from Williams' framework, add momentum confirmation — you can demand that the Awesome Oscillator agrees with the trend direction before acting on an eating-phase signal. Outside that toolkit, ADX makes a natural cross-check because a rising ADX confirms the very trend the Gator says is waking up, while a low ADX corroborates the sleeping phase. A simple support-and-resistance read or a higher-timeframe trend filter keeps you trading eating-phase breakouts in the direction of the larger structure. Volume can corroborate expansion, since a genuine trend waking up often comes with rising participation.
Where it fails
The Gator only describes the spread of the Alligator's lines, so it is a context tool and never a standalone entry trigger — using it as one is the most common mistake. Because the Alligator is built from smoothed and forward-displaced averages, both it and the Gator lag the actual turn, so the eating phase confirms a trend only after it is well underway and the sated phase can appear after much of the move is already given back. In persistently choppy markets the histograms flip between small red and small green repeatedly, producing a stream of false awakenings that lead nowhere. The forward shift can also mislead newcomers who forget the lines are plotted ahead of price. The defences are to treat the Gator purely as a phase filter, combine it with the Alligator for direction and a momentum tool for confirmation, and ignore its signals entirely when the bars are small and the market is clearly asleep.
A worked example
Imagine the Alligator's three lines are converging out of a range: the Jaw sits at 100.0, the Teeth at 101.0, and the Lips at 102.5, with the Lips on top in bullish order. The Gator's upper histogram is the absolute gap between Jaw and Teeth, |100.0 − 101.0| = 1.0, and its lower histogram is the negative absolute gap between Teeth and Lips, −|101.0 − 102.5| = −1.5. If on the prior bar those gaps were only 0.6 and −0.9, then both bars have grown, so both print green — the market has moved from awakening into the eating phase. A trader using the phase-gated approach would now take long setups aligned with the Lips-over-Teeth-over-Jaw order, trailing behind the Lips. Several bars later, if the gaps shrink back toward 0.4 and 0.7 and both bars turn red, the Gator has entered the sated phase, warning that the trend is losing appetite and it is time to tighten stops or step aside.