Knowledge center · Technical analysis
On-balance volume
A running total that adds volume on up days and subtracts it on down days — does volume back the price move?
Formula
OBV += volume on up closes; OBV −= volume on down closes.
Interpretation
When OBV rises with price, real participation backs the move. When price rises but OBV falls, the advance is happening on thin conviction — a classic warning.
What good looks like
OBV confirming price direction over the last month.
What bad looks like
OBV diverging from price — moves without sponsorship reverse more often.
Typical range
Unbounded running total — only its direction matters.
Limitations
One heavy day can distort it; gaps and index-rebalance days add noise.
How OmniSignal uses it
Volume is the only direct footprint of institutional participation available in free daily data.
Where it enters the score
Not a scoring input — drives the volume-confirmation regime shown above.
References
Granville (1963), New Key to Stock Market Profits
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