On-Balance Volume (OBV)
OBV is a cumulative indicator that adds volume on up days and subtracts it on down days—revealing whether volume is flowing into or out of an asset before price reflects it.
What is On-Balance Volume?
Created by Joe Granville in 1963, On-Balance Volume was one of the first momentum indicators to incorporate volume. The theory is simple: volume precedes price. When smart money moves into or out of a stock, OBV will show it before the price trend changes.
Unlike price-based indicators, OBV focuses purely on volume flow. A rising OBV indicates that volume is heavier on up days, suggesting accumulation. Falling OBV means volume is heavier on down days, suggesting distribution.
Rising OBV
Volume flowing in. Buying pressure exceeds selling pressure—bullish signal.
Falling OBV
Volume flowing out. Selling pressure exceeds buying pressure—bearish signal.
How It Works
OBV calculation is straightforward. It keeps a running total that adds the entire day's volume when price closes up, and subtracts it when price closes down.
If Close > Previous Close:
OBV = Previous OBV + Current Volume
If Close < Previous Close:
OBV = Previous OBV - Current Volume
If Close = Previous Close:
OBV = Previous OBV (unchanged)
The absolute value of OBV doesn't matter—what matters is its direction and whether it confirms or diverges from price action.
Trend Confirmation
The primary use of OBV is confirming price trends. When OBV moves in the same direction as price, it validates the trend's strength.
Bullish Confirmation
- Price making higher highs AND OBV making higher highs
- Strong uptrend with volume support
- Safe to add to long positions
- Trend likely to continue
Bearish Confirmation
- Price making lower lows AND OBV making lower lows
- Strong downtrend with volume support
- Avoid buying dips
- Consider short positions
OBV Divergences
The most powerful OBV signals come from divergences—when OBV and price move in opposite directions. This often precedes major trend reversals.
Bullish Divergence
Price makes lower lows but OBV makes higher lows. Accumulation occurring despite falling prices.
Bearish Divergence
Price makes higher highs but OBV makes lower highs. Distribution occurring despite rising prices.
Divergences are leading signals. A bearish divergence at a top warns that smart money is selling into strength. A bullish divergence at a bottom shows accumulation before a potential reversal.
Breakout Signals
OBV can confirm or reject breakouts by showing whether volume supports the move. This helps filter false breakouts.
Valid Breakout
- Price breaks above resistance
- OBV also breaks to new highs
- Volume confirms the move
- Enter with confidence
False Breakout Warning
- Price breaks above resistance
- OBV fails to confirm (stays flat or falls)
- Lack of volume support
- Wait for confirmation or avoid
Pro Tip
Apply a moving average to OBV (like 20-period) to smooth out noise and identify the overall trend more easily. OBV crossing above/below its MA can generate cleaner signals.
Frequently Asked Questions
What is On-Balance Volume (OBV)?
OBV is a cumulative volume indicator that adds volume on up closes and subtracts volume on down closes. It shows whether volume is flowing into or out of an asset. Rising OBV confirms uptrends; falling OBV confirms downtrends.
How do I use OBV for trend confirmation?
When price and OBV move in the same direction, the trend is confirmed. If price rises but OBV falls (or flattens), the rally may lack volume support and be vulnerable. Use OBV to validate breakouts and trend strength.
What is OBV divergence?
Bullish divergence: price makes a lower low but OBV makes a higher low—selling pressure may be weakening. Bearish divergence: price makes a higher high but OBV makes a lower high—buying pressure may be fading. Divergence can precede reversals.
Can OBV confirm breakouts?
Yes. A valid breakout often has OBV breaking to new highs (for upside) or new lows (for downside) with price. If price breaks but OBV does not confirm, the breakout may fail. Use OBV to filter false breakouts.
Should I use a moving average with OBV?
Applying an MA (e.g. 20-period) to OBV smooths noise and clarifies trend. OBV crossing above its MA can signal accumulation; crossing below can signal distribution. This can generate cleaner signals than raw OBV alone.