Double Top & Double Bottom Guide

At a glance

Structure: Two highs at a similar level with a trough between
Trigger: A close below the intervening trough
Why it works: Supply appeared twice at the same price
Main failure: The third attempt succeeds, trapping shorts

Key takeaways

The pattern is objectively definable: two swing highs within a tolerance band, separated by a trough of meaningful depth.
The mechanism is straightforward: sufficient supply appeared at a price twice, and buyers failed to absorb it.
The trigger is the break of the trough between the peaks, not the second peak itself.
Each test consumes resting orders, so a third test is more likely to break through than the first two were.
Failed double tops produce sharp advances as trapped shorts cover, which is why the invalidation level must be respected.

An objective definition

Swing identification: A swing high is a bar whose high exceeds those of the 5 bars either side. Mechanical, with no drawing involved.
Peak tolerance: The two swing highs must be within 3 percent of each other, or within 0.5 ATR for a volatility-scaled version.
Trough depth: The intervening low must be at least 5 percent below the peaks, or 2 ATR, so that a minor pullback does not qualify.
Time separation: The two peaks must be separated by at least 10 bars and no more than 120, which prevents matching unrelated points.
Prior trend: A meaningful advance must precede the first peak. Without it, the structure is a range boundary rather than a reversal.
Trigger: A daily close below the intervening trough.
Invalidation: A close above the higher of the two peaks.
Target: The distance from the peaks to the trough, projected downward from the trigger level.

Every element is numeric, which means the pattern can be scanned for and its base rate measured. That puts it among the more testable of the classical patterns, alongside range breakouts and failed breaks.

What it represents

A price level attracts sellers. Buyers push price into it, supply appears, and price retreats. Buyers try again, supply appears again, and price retreats again. The second failure is informative because it demonstrates that the supply was not a one-off.

Who is selling. Participants with a cost basis near that level who want out at breakeven, holders taking profit, or a large seller working an order over time.
Who is now trapped. Buyers who entered on the second approach, expecting a breakout, are underwater as price falls back toward the trough.
Where the stops are. Below the intervening trough, which is why the break through it accelerates.
Why volume matters. Lower volume on the second peak than the first suggests weaker buying interest and supports the structure.
Why the third test is different. Two tests have consumed supply. If a third attempt comes with expanding volume, it frequently succeeds, which is why the invalidation rule matters.

Trading the pattern

1
Confirm a prior advance
Without a meaningful move into the level, there is nothing to reverse, and the structure is more likely a range boundary.
2
Wait for the trough break on a closing basis
The second peak alone is not a signal. Many second peaks are followed by a third attempt that succeeds.
3
Enter on the break or on the retest of the trough level
The retest, where broken support acts as resistance, offers a tighter stop and better risk-reward when it occurs.
4
Stop above the second peak
Or above the midpoint between the trough and the peaks for a tighter version, accepting a higher failure rate.
5
Take partial profit at the measured move
Peak-to-trough distance projected from the break. Trail the remainder rather than exiting fully.
6
Check volume
Lower volume on the second peak and expanding volume on the break both support the structure, though neither is required.

Failure modes

Failure	What happens	How to reduce it
Third test succeeds	Price breaks above both peaks, squeezing shorts	Honour the invalidation; size for the gap risk
Break fails immediately	Close back above the trough within two bars	Use a time stop; exit on the reclaim
Peaks too far apart	Unrelated highs matched by a loose definition	Enforce a maximum time separation
Trough too shallow	A minor pullback counted as a pattern	Require meaningful trough depth in ATR terms
No prior trend	A range boundary mistaken for a reversal	Require a preceding advance
Pattern within a strong uptrend	Counter-trend short in a rising market	Apply a higher-timeframe trend filter

The double bottom

The mirror image at the end of a decline: two lows at a similar level with a peak between, triggered by a close above the intervening peak. The mechanism is the same, with demand appearing twice at a price.

In equity markets, double bottoms have a structural advantage over double tops, because the long-term drift of indices is upward. Tests that separate the two directions frequently find the bullish version performs better, which reflects the market environment rather than the pattern itself. The same asymmetry appears in most reversal patterns.

Frequently asked questions

How exact do the two peaks need to be?

Within a few percent, or within half an ATR for a volatility-scaled definition. Exact equality is not required and rarely occurs. What matters is that the market treated the two prices as the same level, which a tolerance band captures better than a precise match.

When is the entry, at the second peak or at the break?

At the break of the intervening trough, on a closing basis. Entering at the second peak means anticipating a pattern that has not confirmed, and many second peaks are followed by a successful third attempt. The trough break is the point at which the structure is complete.

What is the target for a double top?

The conventional measured move projects the peak-to-trough distance downward from the break level. It is a reasonable first target and a convention rather than a statistical expectation. Scaling out there and trailing the remainder handles both the frequent case where it is reached and the occasional case where the move extends much further.

Are triple tops more reliable than double tops?

Not necessarily. Each test consumes resting supply, so a level that has been tested three times may be closer to breaking than one tested twice. Triple formations are also rarer, so the sample available for evaluation is smaller. The additional test is information, but not necessarily reassuring information.

Do double tops work in crypto?

The structure appears, but moves extend much further and reversals are more violent, so stops must be wider and positions smaller. The higher incidence of liquidation cascades also means breaks can overshoot the measured move substantially in both directions, which argues for trailing rather than fixed targets.

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Referenced by

Head and Shoulders Pattern: Definition, Mechanism, and Honest Testing

Educational use only. This guide explains how a strategy works. It is not investment advice, not a recommendation, and no result described here is a forecast. Test any approach on historical and out-of-sample data, size positions conservatively, and never risk money you cannot afford to lose.