Quick floating web calculator — webcalculator

Add a compact, floating calculator to any webpage—perfect for quick calculations while browsing.
This Firefox extension was inspired by the clean and efficient interface of www.web電卓.jp, a popular web-based calculator in Japan.

With this extension, you can:

Launch a simple calculator with one click

Use it without switching tabs

Perform basic arithmetic (+, –, ×, ÷) directly on any site

Quickly close or reopen it as needed

Enjoy a smooth, non-intrusive user experience

Whether you're comparing prices, working on online spreadsheets, or studying math, this calculator stays with you—right on the page.