how to calculate trailing stop loss?

A trailing stop loss order can be set as a fixed percentage or dollar amount below the highest price that the security has reached.

To calculate a trailing stop loss using a percentage, you would first determine the highest price the security has reached and then multiply that price by the percentage you want the stop loss to trail the security by. For example, if the highest price of a security is Rs100 and you want to use a trailing stop loss of 5%, you would multiply Rs100 by 5% to get Rs 5. This means that your stop loss would be triggered if the security's price falls to Rs 95 or lower.

To calculate a trailing stop loss using a dollar amount, you would again determine the highest price the security has reached and then subtract the dollar amount you want the stop loss to trail the security by. For example, if the highest price of a security is Rs100 and you want to use a trailing stop loss of Rs5, you would subtract Rs 5 from Rs 100 to get Rs 95. This means that your stop loss would be triggered if the security's price falls to Rs 95 or lower.

You need to keep track the highest price and update the stop loss price accordingly, some trading platform do it automatically. It is important to mention that trailing stop loss is not a guarantee to limit loss and profit, it is an order that help you define an exit strategy that adjusts to the security price.