I Built the World's Most Customizable Scientific Calculator (30+ Themes, Python + PyQt6)

Description and use

ACALCU v3 is a scientific calculator with 30+ themes and per‑button customization, built with Python and PyQt6.

Problem

Standard OS calculators lack visual variety and personalization, leading to a dull user experience.

Outcome

ACALCU v3 demonstrates how a simple scientific calculator can be transformed into a highly personalized tool, encouraging user engagement through extensive theming and customization options.

Workflow

• Define theme dictionaries with colors, fonts, and flags.
• Implement a Config class to merge active theme and per‑button overrides.
• Create a ButtonCustomizer dialog for right‑click styling and media attachment.
• Build a simple expression engine mapping button clicks and keyboard input to Python math functions.
• Render the UI by applying computed stylesheets to widgets.
• Persist customizations in a local JSON file and reload on launch.
• Provide a history dialog for recent calculations.
• Expose the app as a single‑file executable.
• Publish the source on GitHub for community theme contributions.

Evidence

The whole thing is a single-file PyQt6 desktop app, structured around a few core pieces:

Source

30+ built-in themes — Royal, Liquid Glass, Wild, Cyberpunk, Dracula, Nord, Solarized, Monokai, Windows 7 / Vista / 10, OneUI 8.0, Matrix, Rose Gold, Galaxy, Fire, Ice, Neon, Vintage, Sakura, Midnight, Forest, Candy, Terminal, Gold Dark, and more.

Source