Breakout (new N-day high or low)

A breakout is when a stock closes at a new high or low over a lookback window (e.g. 20 or 55 days), pushing beyond its recent trading range.

A breakout happens when a stock’s closing price moves beyond the boundary of its recent range — for example a new 20-day or 55-day high (an upside breakout) or low (a downside breakout). The idea, popularized by Donchian-channel trading, is that clearing a well-established level marks a potential change in the balance of supply and demand.

Breakouts are prone to "false breaks," where the price pokes past the level and then reverses. Some traders look for confirmation from heavier-than-usual volume on the breakout day, on the theory that a move backed by volume is more likely to hold.

stocks-llm flags new N-day highs and lows (Donchian 20/55) nightly, and a volume-confirmed variant. A breakout describes a price event that has already occurred; it is not a prediction or a recommendation.

Stocks breaking out to new highs →

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Informational only — NOT financial advice. This is an educational definition, not a recommendation to buy or sell anything. Metrics on stocks-llm are delayed data and may be missing or stale. Always verify information independently and consult a qualified financial professional before making any investment decision.