There is more to Pro Office Calculator than meets the eye. Look for subtle clues to unlock its secrets. You may be surprised how deep the rabbit hole goes.

Inspired by the Easter eggs found in old office software, e.g. Excel 95, I wanted to create something that was almost entirely Easter egg, the calculator being merely a facade into this hidden layer.

Pro Office Calculator features a Doom-style 3D engine written from scratch specifically for this project.

The game is hard. Some puzzles may require a pencil and paper.

Here is a clue to get you started: You may want to take a break and come back to it ;)