Following this article, you will know how to:
- Setup a Magento shop with multiple currency.
- Setup currency rate
First of all, please note that I am using Magento 188.8.131.52 for my article. There might be some differences in other versions. Now, log in your backend and go to System > Configuration > General and open Currency Setup. Here you can setup available currencies for your store. Remember to select default and base currency as well.
Now, you can go to System > Manage Currency Rates to configure rate between currencies.
That's it. You are done.