There's also a button at the bottom to convert the numbers to ISD phone number format. For example, you copy a number online in the format (012345 12345), then you can copy-paste that number in the window input, and select the country that the number should belong to, and the number is converted into (+1 12345 12345) instantly if you select USA/Canada or +91 if you select India. It's a useful app for people who want to whatsapp unknown numbers without adding them to their mobile address book.