A modern, transparent Singapore tax calculator for personal and corporate income tax estimation.
Personal Tax & Corporate Tax Calculators
NovaTax SG is a client-side Singapore tax estimation tool that provides transparent, step-by-step breakdowns based on official IRAS tax rates and rules. Designed for learners, business users, and working professionals.
| Feature | Description |
|---|---|
| Personal Income Tax | Progressive tax brackets (0%–24%), resident & non-resident modes, 10+ relief categories |
| Corporate Income Tax | Flat 17% rate with Partial & Start-Up exemptions, CIT rebates by YA |
| Real-Time Calculation | Results update instantly as you type — no submit buttons |
| Transparent Breakdown | Bracket-by-bracket and step-by-step tax logic with visual bar charts |
| Stats Dashboard | At-a-glance stat cards for key tax figures |
| Dark / Light Theme | Polished dual-theme with system preference detection and localStorage persistence |
| Responsive Design | Dashboard-style layout that adapts cleanly to desktop, tablet, and mobile |
| Data Persistence | Form inputs saved to localStorage across sessions |
| Print-Friendly | Clean print view for exporting tax summaries |
| IRAS-Aligned | Based on official Singapore tax rates, exemption schemes, and rebate rules |
| Layer | Technology |
|---|---|
| Markup | HTML5 (semantic, accessible) |
| Styling | CSS3 (custom properties, responsive grid, dark/light theming, Inter font) |
| Logic | Vanilla JavaScript (ES6+, no frameworks) |
| Hosting | GitHub Pages (static, zero build step) |
┌─────────────────────────────────────────────────┐
│ Browser │
├──────────┬──────────┬──────────┬────────────────┤
│ index │ personal │corporate │ about │
│ .html │ -tax.html│ -tax.html│ .html │
├──────────┴──────────┴──────────┴────────────────┤
│ css/styles.css │
│ (CSS custom properties, dashboard UI) │
├─────────────────────────────────────────────────┤
│ js/theme.js │ js/common.js │
│ (dark/light) │ (utils, nav, format, validate) │
├───────────────┼─────────────────────────────────┤
│ js/personal- │ js/corporate- │
│ tax.js │ tax.js │
│ (progressive │ (flat rate, │
│ brackets, │ exemptions, │
│ reliefs) │ rebates) │
├───────────────┴─────────────────────────────────┤
│ js/data/tax-rates.js │
│ (centralized IRAS rates, brackets, rebates) │
└─────────────────────────────────────────────────┘
novataxsg/
├── index.html # Landing page (hero, calculator cards, features)
├── personal-tax.html # Personal income tax calculator
├── corporate-tax.html # Corporate income tax calculator
├── about.html # Tax rules, FAQ, assumptions
├── css/
│ └── styles.css # Dashboard-style stylesheet (light + dark themes)
├── js/
│ ├── data/
│ │ └── tax-rates.js # Centralized IRAS tax data
│ ├── common.js # Shared utilities (formatting, validation, nav)
│ ├── theme.js # Dark/light toggle with persistence
│ ├── personal-tax.js # Personal tax calculator logic
│ └── corporate-tax.js # Corporate tax calculator logic
├── assets/
│ ├── screenshot.png
│ ├── screenshot-personal-tax.png
│ └── screenshot-corporate-tax.png
└── .gitignore
- Any modern web browser (Chrome, Firefox, Safari, Edge)
- No build tools, frameworks, or dependencies required
# Clone the repository
git clone https://github.com/alfredang/novataxsg.git
cd novataxsg
# Open directly in browser
open index.html
# Or serve with any static server
python3 -m http.server 8080
# Then visit http://localhost:8080This project is deployed on GitHub Pages with zero configuration:
- Push to
mainbranch triggers automatic deployment - No build step required — all files are static HTML/CSS/JS
- Live at: https://alfredang.github.io/novataxsg/
- Progressive rates from 0% to 24% (YA 2024 onwards)
- Supports 10+ relief categories (CPF, spouse, children, parent, NSman, donations, SRS, etc.)
- Non-resident mode: 15% flat on employment (or progressive, whichever higher) + 22% on other income
- Flat rate: 17%
- Partial Tax Exemption: 75% on first $10k + 50% on next $190k
- Start-Up Tax Exemption: 75% on first $100k + 50% on next $100k (first 3 YAs)
- CIT Rebates: YA 2024 (50%, cap $40k) · YA 2025 (50%, cap $40k) · YA 2026 (40%, cap $30k)
Disclaimer: This tool provides estimates for educational purposes only. Always verify with official IRAS guidance before filing.
Contributions are welcome!
- Fork the repository
- Create a feature branch:
git checkout -b feature/my-feature - Commit changes:
git commit -m "Add my feature" - Push to branch:
git push origin feature/my-feature - Open a Pull Request
Tertiary Infotech Academy Pte Ltd
- IRAS — Official Singapore tax rates and calculator references
- Built with vanilla HTML, CSS, and JavaScript — no frameworks, no dependencies
If you find this useful, give it a star!