Bill Williams believed markets trend only a fraction of the time and spend the rest chopping sideways — and that most traders lose money by trading the chop as if it were a trend. His Alligator indicator, introduced in "Trading Chaos", is a visual answer to one question: is the market sleeping, or is it hunting?
The three lines
The Alligator plots three smoothed moving averages (SMMA) of the median price — (High + Low) / 2 — each shifted forward into the future:
Two details trip people up. First, these are smoothed moving averages, which react more slowly than the simple or exponential MAs most platforms default to — swapping in an EMA changes the indicator's behavior. Second, the forward shift means the lines you see beside the latest candle were computed from older data; the offset exists to visually separate the phases, not to predict the future.
The metaphor: sleeping, waking, eating
Williams described the market through the animal's day:
How Williams actually traded it
The Alligator was never meant to stand alone. In Williams' framework it pairs with his fractals: a valid buy fractal (a 5-bar pattern with the highest high in the middle) only becomes an entry if it sits above the Alligator's Teeth; a sell fractal only counts below the Teeth. That single filter is the point of the system — it forbids breakout entries inside the sleeping phase, where they usually fail. The Awesome Oscillator, another Williams tool, then gauges the momentum behind the move.
A practical baseline setup:
The three lines
The Alligator plots three smoothed moving averages (SMMA) of the median price — (High + Low) / 2 — each shifted forward into the future:
- Jaw (blue): 13-period SMMA, shifted 8 bars forward. The slowest line — the long-term balance level.
- Teeth (red): 8-period SMMA, shifted 5 bars forward. The intermediate line.
- Lips (green): 5-period SMMA, shifted 3 bars forward. The fastest line.
Two details trip people up. First, these are smoothed moving averages, which react more slowly than the simple or exponential MAs most platforms default to — swapping in an EMA changes the indicator's behavior. Second, the forward shift means the lines you see beside the latest candle were computed from older data; the offset exists to visually separate the phases, not to predict the future.
The metaphor: sleeping, waking, eating
Williams described the market through the animal's day:
- Sleeping — the three lines are intertwined and flat, price crossing back and forth through them. This is the range. The longer the Alligator sleeps, the hungrier it gets — extended congestion tends to precede a stronger expansion.
- Waking — the Lips cross above (or below) the Teeth and Jaw, and the lines begin to fan apart in order: green, red, blue. This is the earliest hint that a trend is forming.
- Eating — the lines are cleanly separated and pointing the same way, with price riding outside the Lips. This is the tradable trend phase: longs above an upward fan, shorts below a downward one.
- Sated — the lines flatten and start to converge again. The move is ending; Williams took this as the cue to exit, not to add.
How Williams actually traded it
The Alligator was never meant to stand alone. In Williams' framework it pairs with his fractals: a valid buy fractal (a 5-bar pattern with the highest high in the middle) only becomes an entry if it sits above the Alligator's Teeth; a sell fractal only counts below the Teeth. That single filter is the point of the system — it forbids breakout entries inside the sleeping phase, where they usually fail. The Awesome Oscillator, another Williams tool, then gauges the momentum behind the move.
A practical baseline setup:
- Wait for a genuine sleeping phase to end — lines fanning out in order, price closing outside the Lips.
- Enter on the break of the most recent fractal on the trend side of the Teeth.
- Trail the stop behind the Teeth (aggressive) or the Jaw (conservative); a close back through the Jaw is the strongest exit signal.
Limitations to respect
Everything here is built from moving averages, so the Alligator is a lagging indicator: it confirms trends, it does not anticipate them, and the forward displacement does not change that. In persistent ranges it produces repeated false awakenings — the fan opens for a few bars and collapses again — which is why the fractal filter and some patience with the "order" of the lines matter more than the crossings themselves. It is at its best on liquid instruments and higher timeframes (H1 and up), where ranges and trends are cleanly separated; on very fast charts the constant intertwining makes it nearly unreadable.
If you already trade with the Awesome Oscillator or fractals, the Alligator is the missing piece that tells you when those signals are allowed to count. Do you use the full Bill Williams toolkit, or just parts of it? Tell us how you combine them below.