Williams Fractals: marking the swing highs and lows mechanically
How fractals define a swing point with a fixed rule, why they always appear two bars late, and what they are actually good for.
Williams Fractals 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
A fractal marks a bar whose high is higher than the two bars either side of it, or whose low is lower than both neighbours. It is a mechanical definition of a swing point.
The value is that it removes judgement. Two people looking at the same chart will disagree about where the swing highs are; the fractal rule gives one answer.
It is a labelling tool rather than a signal. What you do with the marked points — draw a level, place a stop, define a structure — is where the trading decision lives.
How it is calculated
These are the steps Basis performs, verified against the published definition.
- 1
For each bar, look at the two bars before it and the two after it.
- 2
If its high exceeds all four, mark an up fractal at that high.
- 3
If its low is below all four, mark a down fractal at that low.
- 4
A bar can be both, and in a very quiet market frequently is.
Settings
| Setting | Default | Range |
|---|---|---|
| Bars each side | 2 | 1 – 10 |
Two bars either side is the standard and most implementations do not expose it. Widening it to three or more produces fewer and more significant swing points at the cost of confirming even later.
How to read it
- The most recent confirmed fractal high is the level a breakout would have to clear, which makes it a natural stop or entry reference.
- A sequence of higher fractal lows is an uptrend defined without drawing anything.
- Fractals cluster in ranges and thin out in trends, which is itself a read on conditions.
- They mark where price turned, not where it will turn.
Where it misleads
A fractal needs two bars after it to be confirmed, so it can never appear on the current bar and always arrives two bars late. That is not a defect — it is what makes the definition unambiguous — but it means any system using fractals is acting on information that is at minimum two bars old, and a backtest that marks fractals on the last bar of its data is reading the future. Basis confirms them properly, which is why the most recent swing often has no fractal on it yet.
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Updated 2026-08-22 · Educational reference, not financial advice.