Volatility

Average True Range (ATR)

A pure measure of how much price moves — the foundation of volatility-based stops and sizing.

ATR (Average True Range) answers one question with no directional opinion: how much does this market move in a typical period? It averages the 'true range' (the full high-to-low move, including any gap) over a lookback, giving a single number in price terms. A BTC ATR of $1,500 means a typical bar covers about $1,500 of range.

Why it is so useful

  • Stops — place a stop a multiple of ATR away (e.g. 1.5×ATR) so it sits beyond normal noise and only triggers on a real move against you.
  • Targets — size profit objectives in ATR units to keep risk:reward consistent across calm and wild markets.
  • Sizing — adjust position size to ATR so each trade risks the same dollar amount regardless of volatility (next lesson).
  • Context — a rising ATR means the market is heating up; a falling ATR means it is calming.

The key insight

A fixed-dollar or fixed-percent stop is a mistake, because the same stop is far too tight in a wild market and needlessly wide in a calm one. ATR makes your stops and targets adapt to current conditions automatically. This is exactly how this project's own engine sizes risk — stops are set at a multiple of each agent's entry ATR, not a fixed number.

Notes

ATR is direction-blind — a high ATR says 'big moves', not 'up' or 'down'. It also lags, as an average of past ranges, so a sudden volatility spike takes a few bars to fully register. Use it as the volatility input to your risk decisions, paired with directional tools for the trade itself.

Check your understanding

  1. 1. ATR measures…

  2. 2. A common use of ATR is to place…

  3. 3. Why is a fixed-dollar stop a mistake?

  4. 4. A rising ATR means the market is…

  5. 5. ATR tells you about direction…

Answer all 5 to check