What is Call Open Interest? The call open interest refers to the total amount of OI (open interest) across calls. This can be the total call OI on one strike, as separated from put OI. It can also be the total call OI for an entire option chain, or for a security across all option chains. Related articles What is Put Open Interest? What is 25D Risk Reversal? What does each axis on the HIRO Chart represent?
