Regularly updated currency converters that allow conversion between U.S. dollars and Iranian rial are available at Onada.com and XE.com. Both sites allow users to see how many rial equate to a given amount in dollars, as well as view the current conversion rate.
When reading an exchange rate, the first currency listed always stands for one unit of that currency, while the second currency listed is an equivalent to the first. For example, if the exchange rate of dollars to rial is 28,900, then one U.S. dollar is equal to 28,900 rial. Sometimes, the exchange rate between currencies may vary between financial institutions. This is because the institutions are taking into account currency conversion costs and other fees.