Thanks for joining this thread, @sawback. I'll gladly provide some info about the purpose of currency conversion rate in QuickBooks Online.

When you turn on multicurrency, QuickBooks uses exchange rates to get the home currency values of your foreign currency transactions. QuickBooks uses exchange rates to show how much a foreign currency transaction is in your home currency value.

QuickBooks also uses exchange rates for your reports. This makes sure you have a better view of how your business is doing.

When you enter foreign currency transactions, QuickBooks shows 2 different amounts:

• Total foreign currency amount. QuickBooks multiplies the product or service rate by the exchange rate.
• Total home currency amount. QuickBooks multiplies the total foreign currency amount by the exchange rate.

I'm also adding this resource to guide you on how to enter your own exchange rates in QuickBooks Online.

Feel free to get back to this thread if you have clarifications with the multi-currency features in QuickBooks. I'll make sure to answer them for you. Have a pleasant day.