If you want a tool you can save to your desktop or phone, Google Sheets is the best "downloadable" option. It allows you to track multiple currencies in one place. Open a new Google Sheet. In any cell, type: =1 * GOOGLEFINANCE("CURRENCY:USDEUR") .
Since Google doesn't offer a standalone .exe or .dmg file for currency conversion, you can achieve the same result using these official Google integrations: download google currency converter
For those who want a dedicated icon on their home screen, follow these steps to create a "web app" version of Google's converter: Open your mobile browser and search "Currency Converter." If you want a tool you can save