F&O Margin Calculator

SPAN (Standard Portfolio Analysis of Risk) margin is the minimum margin NSE requires to hold a futures or short options position. The exchange computes it from the worst likely one-day loss on the position across a range of price and volatility scenarios.

Exposure margin is collected on top of SPAN margin as a buffer against moves larger than the SPAN scenarios. For index derivatives it is typically about 2-3% of the contract value; for stock derivatives it is higher.

SPAN margin covers the modelled worst-case one-day loss; exposure margin is an extra cushion above it. The total margin blocked for a futures or option-selling position is SPAN plus exposure.

Selling an option needs roughly the same SPAN plus exposure margin as a futures position on the same underlying, reduced when the position is hedged. Buying an option needs only the premium, with no SPAN or exposure margin.

NSE revises lot sizes periodically. This calculator reads NSE's current lot size for every F&O contract rather than a fixed list, and shows it for the contract you choose.

Intraday (MIS) equity trades require a fraction of the trade value as margin, set by the exchange's peak-margin rules and the broker; delivery (CNC) trades require the full value. The calculator applies typical percentages for each.