**1. Single-currency margin: cross margin**

In single-currency margin mode, the system allows users to open long or short positions of options, as shown in the following figure:

Term | Definition |

Total | The total of long positions is a positive number, and the total of short positions is a negative number. |

Options value | If the unit for calculating the price is currency, then options value = total positions * mark priceIf the unit for calculating the price is the number of contracts, then options value = total positions * mark price * multiplier |

P&L | Unrealized profit or loss of current positionP&L = (mark price - avg. open price) * total positions * multiplier |

P&L ratio | P&L of long positions = (mark price – avg. open price) / avg. open price P&L of short positions = (avg. open price - mark price) / avg. open price |

Initial margin | The initial margin for long positions is 0. As to initial margin of short positions, please refer to Introduction to the calculation of options margin. |

Maintenance margin | The maintenance margin for long positions is 0. As to maintenance margin of short positions, please refer to Introduction to the calculation of options margin. |

**2. Multi-currency margin mode: cross margin**

Under the multi-currency margin mode, the system automatically allows the users to open long and short positions of options. The options positions are shown in the following:

Term | Definition |

Total | The total of long positions is a positive number, and the total of short positions is a negative number. |

Options value | If the unit for calculating the price is currency, then options value = Total positions * Mark price If the unit for calculating the price is the number of contracts, then options value = Total positions * Mark price * Multiplier |

PnL | Unrealized profit or loss of current positions PnL = (Mark price - Avg. open price) * Total positions * Multiplier |

PnL ratio | PnL of long positions = (Mark price – Avg. open price) / Avg. open price PnL of short positions = (Avg. open price- Mark price) / Avg. open price |

Initial margin | The initial margin for long positions is 0. For initial margin of short positions, please refer to Introduction to the calculation of options margin.https://www.OKX.com/support/hc/en-us/articles/360053909092-XIII-Introduction-to-options-margin-calculation |

Maintenance margin | The maintenance margin for long positions is 0. For maintenance margin of short positions, please refer to Introduction to the calculation of options margin.https://www.OKX.com/support/hc/en-us/articles/360053909092-XIII-Introduction-to-options-margin-calculation |

**3. The isolated mode f Single/multi-currency/Portfolio margin**

In isolated margin mode, the system only allows users to open short options positions. The isolated options positions are shown as follows:

Term | Explained |

Total | The total amount of long positions is positive, and the total amount of short positions is negative. |

Options value | Positions * mark price * contract multiplier |

P&L | Unrealized profit or loss of the current positionP&L = (mark price -avg.open price) * total positions * contract multiplier |

P&L ratio | P&L of long positions = (mark price – avg.open price) / avg.open priceP&L of short positions = (avg.open price- mark price) / avg.open price |

Margin balance | Initial margin + manually added or removed margin |

Maintenance margin | The calculation of the maintenance margin for short positions refers to: |

Margin ratio | Margin balance / (maintenance margin + liquidation fee) |