Instant percentage tools and an interactive calculator.
X is what % of Y
What is X% of Y
Percentage change from X to Y
X is P% of what?
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About Percentage & Math Calculator
A comprehensive PWA that combines percentage calculations, a full
standard &
scientific calculator with MathLive WYSIWYG input, 12 themes, and an audit tape — all
running
client-side with zero dependencies on a server.
Tech Stack
HTML5CSS3Vanilla JSMathLiveMath.jsPWA
Security & Architecture
npm-managed dependencies
100% client-side, zero data sent
Service Worker offline cache
localStorage state persistence
Features
4 percentage calc types
Standard + Scientific modes
Memory (M+/MR/MC/M−)
12 themes incl. 4 animated Aurora
Light & dark mode toggle
Audit tape with copy & reuse
Multi-row calculations
Keyboard shortcuts (0-9, +-*/=)
Auto font-sizing & sci notation
Responsive mobile layout
Installable PWA with offline mode
Session state auto-persistence
Limitations
No server, DB, or cloud sync
IEEE 754 float precision
No graphing or unit conversion
Built by Danh Michael Mujar
Business Support Senior Specialist at WTW who believes numbers should be beautiful
and tools
should be transparent. Powered by curiosity, caffeine, and Generative AI.