Williams Alligator: three shifted averages that show when to stay out
How the Alligator uses three displaced smoothed averages to distinguish a trending market from a sleeping one, and why the gaps matter more than the lines.
Williams Alligator is free on Basis — the button opens a live crypto chart with it already applied. No account, no trial and no limit on how many indicators you add.
Open the chartWhat it measures
The Alligator plots three smoothed moving averages of different lengths, each pushed forward in time by a different amount. Bill Williams named them the jaw, the teeth and the lips.
The point is not the lines but the space between them. When they are intertwined the market has no trend and the alligator is asleep; when they separate and fan out in order, it is feeding.
It is one of very few indicators designed primarily to tell you when not to trade, which is why it reads as unhelpful to anyone looking for entries.
How it is calculated
These are the steps Basis performs, verified against the published definition.
- 1
The jaw is a thirteen-period smoothed average of the median price, displaced eight bars forward.
- 2
The teeth are an eight-period smoothed average, displaced five bars forward.
- 3
The lips are a five-period smoothed average, displaced three bars forward.
- 4
The smoothed average used is Wilder-style rather than simple, which is why the lines are calmer than their periods suggest.
Settings
| Setting | Default | Range |
|---|---|---|
| Jaw | 13 | 1 – 500 |
| Teeth | 8 | 1 – 500 |
| Lips | 5 | 1 – 500 |
Thirteen, eight and five with displacements of eight, five and three are fixed by the original and rarely exposed. Changing them turns it into three arbitrary averages and loses the fan geometry the whole reading depends on.
How to read it
- Intertwined lines mean no trend. That is the majority of the time and the indicator is telling you to wait.
- Lines separating with lips above teeth above jaw is an established uptrend; the reverse order is a downtrend.
- The wider the fan, the stronger the move — and a fan that starts to close is a trend losing its structure.
- Price returning to touch the lips during a fanned trend is the conventional continuation entry.
Where it misleads
The forward displacement means the lines you see next to the current bar were computed from data several bars old, and the values plotted ahead of price were computed before that. That is not lookahead — nothing uses future data — but it does mean a backtest reading the line at a bar must use the displaced value that was actually available then, and a naive implementation that reads the undisplaced series will produce results no live trader could have achieved.
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Updated 2026-08-22 · Educational reference, not financial advice.