The number that tells you what "normal" means
Average True Range measures how far an instrument typically moves in one period. It is the only common indicator that measures something price alone does not obviously show you, and it is the one most retail traders never open.
True Range for a candle is the largest of:
- High minus low
- High minus previous close
- Previous close minus low
The last two catch gaps, which is why it is "true" range rather than just the candle's height. ATR is the average of that over N periods, usually 14.
Why it matters more than any oscillator
Everything else you have learned tells you *what* to trade. ATR tells you what counts as noise on this instrument, right now.
That single number answers questions no chart pattern can:
- Is my stop inside normal movement, or beyond it?
- Is this instrument behaving unusually today?
- What size can I take if the stop has to be this wide?
- Is my target realistically reachable in the time I plan to hold?
A trader who checks ATR before every trade will avoid most of the stop-outs that feel unfair.