Calculator Whiz & Custom Web Search is an extension designed for Firefox that combines a comprehensive online calculator with a customizable web search experience. Users can perform basic calculations like addition and subtraction, as well as more complex operations using a scientific calculator. The financial calculator feature allows users to calculate loan payments and interest rates, enhancing its utility for personal finance management. This extension is subscription-based and offers a seamless integration into the browser for quick access to essential tools.

In addition to its calculator capabilities, the extension provides a custom web search function, utilizing Yahoo as the default search provider. Users can initiate searches directly from the browser's search box, receiving a variety of results including news, images, and videos. The installation process is straightforward, and users can easily access the calculators through the toolbar icon. With a focus on user experience and data privacy, the extension ensures that personal information is handled responsibly.