Open Interest Explained
Open interest, or OI, shows the number of outstanding derivative contracts that remain open. In index options, OI helps traders identify where large call and put positions are concentrated.
Key Takeaways
- OI shows positioning, not certainty.
- High call OI can mark potential resistance.
- High put OI can mark potential support.
- Change in OI can show where fresh positioning is building.
- OI must be read with price action and expiry context.
Call OI And Put OI
| OI Type | Common Use |
|---|---|
| Call OI | Helps identify resistance or supply zones |
| Put OI | Helps identify support or demand zones |
| Change in OI | Helps identify fresh additions or unwinding |
For Nifty and Bank Nifty, the highest OI strikes often become important reference points during the session.
OI Concentration
OI concentration means a large amount of open interest is clustered at one or more strikes. This can show where traders are positioning for expiry or where hedging activity is visible.
Example questions:
- Which strike has the highest call OI?
- Which strike has the highest put OI?
- Are new positions being added or unwound?
- Is price moving toward or away from high OI zones?
Common Mistakes
- Assuming high OI always holds.
- Ignoring change in OI.
- Ignoring price closing behavior.
- Treating OI as a fixed level when it can change intraday.
Practical Use In Daily Reports
Open interest is most useful when a report connects:
- price,
- support/resistance,
- PCR,
- max pain,
- volatility,
- and confirmation levels.
Disclaimer
This content is for educational and informational purposes only. It is not investment advice, trading advice, or a buy/sell recommendation. Please consult a registered financial advisor before making any financial decision.
Disclaimer
Educational and informational purposes only. Not investment advice. Consult a registered financial advisor before making trading or investment decisions.