What's stop-loss?

Of course, your forecast may be incorrect, and the transaction after using the currency converter will not be profitable. You can, according to your own criteria, establish the limit to which the transaction opened by You may incur. 

For example, you opened a deal for $ 100 to increase the dollar against the euro. The agreement turned out not to be profitable, and the dollar falls against the euro. But You have decided that the loss must not exceed 10% of the money you have invested in your operation, and previously established in the Internet trading platform of the corresponding order - to close the transaction in case of loss of 10% ( this is called stop loss). In this case, the loss of 10% of the funds invested in the agreement will close automatically, only $ 10 is lost. 

Therefore, by using stop loss, you can establish the loss levels acceptable to you.