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RPN calculator v1.1.0


RPN calculator is a web implementation of a reverse polish notation calculator. You push numbers to stack first, then press operator keys which will pop number from stack and run the calculation. For example, you may press num1, return, num2, num3, return, plus, and you will see result 24 in top of stack. Number is pushed to stack using return key.

Supported operators are: +, -, *, /, square-root, power, sum-all. Utility features include delete number, duplicate number, swap top 2 number on stack, undo, clear stack. Hover over button to see what that button does and the hotkey for that button.

This program should work on desktop and mobile browser. Tested in chrome and firefox.


This project is inspired by emacs calc mode. It tries to mimic the behavior when possible.

Debug Features

This website use service worker to make it work offline. If the local cache does not work for some reason, you may force refresh page to get latest version. You may also purge all service worker cache.