What is the On-Balance Volume (OBV) Indicator?
The On-Balance Volume (OBV) Indicator is a cumulative volume indicator that tracks buying and selling pressure by adding volume on up closes and subtracting volume on down closes. It plots as a single running line in a separate panel below the price chart, and traders focus on the line’s direction, swing highs/lows, and whether it confirms price. OBV has no fixed range (it doesn’t oscillate between set levels), so the slope and relative structure matter more than the absolute value.
How is the On-Balance Volume (OBV) Indicator Calculated?
The OBV line updates each bar based on the current close versus the prior close, starting from an arbitrary base value (often 0). The calculation uses three rules:
If Close(t) > Close(t-1): OBV(t) = OBV(t-1) + Volume(t)
If Close(t) < Close(t-1): OBV(t) = OBV(t-1) − Volume(t)
If Close(t) = Close(t-1): OBV(t) = OBV(t-1)
How to Use the On-Balance Volume (OBV) Indicator in Trading?
To use OBV in trading, treat it as a participation and pressure filter: price moves that align with OBV have stronger underlying demand/supply than price moves OBV fails to confirm. The cleanest reads come from confirmation, divergence, and breakouts around obvious levels.
Trend confirmation: price up + OBV making higher highs/higher lows signals accumulation supporting the uptrend; price down + OBV making lower lows/lower highs signals distribution supporting the downtrend.
Divergence: price makes a higher high while OBV makes a lower high flags weakening demand; price makes a lower low while OBV makes a higher low flags fading sell pressure.
Breakout validation: a resistance break with OBV pushing to a new swing high shows aggressive participation; a breakout with flat/falling OBV signals thin follow-through and higher failure risk.
Stops and invalidation: place the stop where the price setup fails (below the breakout retest, below support, or beyond the swing), then manage the trade by watching whether OBV keeps trending in the trade direction or starts diverging.