Currencies and exchange rates
Which currencies the catalog and invoices support, how automatic conversion works, and the /currency rate command.
Catalog currencies
/catalog currency picks which of USD, EUR and INR the catalog shows and which one is primary. A product can have a separate price for each (price_usd, price_eur, price_inr on /catalog product-add), or you set only the primary price and turn on auto_currency so the other two are converted from live rates.
no_price_text is what the catalog shows when a product has no price, for example "Ask in a ticket".
Invoice currencies
/invoice create accepts USD, INR, EUR and GBP. The invoice image and the sales report use the currency you picked; there is no conversion on invoices, so a sale in EUR stays in EUR in the report and /invoice top-buyers ranks per currency.
Where the rates come from
Rates are fetched from a public exchange-rate API with a second provider as fallback, and cached for 5 minutes (EXCHANGE_RATE_CACHE_SECONDS on the host). If both providers fail, converted prices keep the last cached value; if there is none, the catalog shows only the primary price.
/currency rate
A public command anyone can run: /currency rate amount:50 currency:EUR shows that amount in USD, INR, EUR, GBP, JPY, CAD, AUD, CHF, CNY, SGD and AED. Handy in a ticket when a buyer pays in a different currency than the listing.
Rates are informational. The amount you actually receive depends on your payment provider's rate and fees.