3+
Years in software development
100+
Regional calculators shipped
BCA
IGNOU graduate
Executive bio
Sameer Rayeen is a software developer and technical contributor behind Reverse Sales Tax Calculator. With a BCA from Indira Gandhi National Open University and three years of hands-on development experience, he focuses on building fast, accessible calculator tools that run cleanly in the browser. His work spans PHP backends, JavaScript logic, responsive layouts, and the kind of small UX details that make financial tools feel trustworthy on mobile and desktop alike.
Good software disappears into the task. When someone splits tax from a receipt in under a second, that is the standard I build toward—accurate logic, honest copy, and interfaces that respect people's time.
About the author
I got into web development because I liked seeing ideas become something people could actually use the same day. Tax calculators sound niche, but they are a perfect engineering puzzle: precise math, clear inputs, zero confusion, and performance that does not lag on an old phone. On this site, I implement calculator logic, maintain regional pages, and write technical content that explains how the tools work without drowning readers in jargon.
Core expertise
- PHP development
- Frontend development
- JavaScript
- Responsive UI development
- Web application architecture
- SEO-focused web development
- Performance optimization
- Calculator tool development
- SaaS UI implementation
- API integrations
- Technical problem solving
Specialties
- Browser-based financial calculators
- Extensionless URL & clean routing
- Accessible form design
- Client-side calculation pipelines
- Cross-browser QA for math tools
Technologies
- PHP 8
- JavaScript
- HTML5 & CSS3
- Apache / Nginx
- Git
- Structured data (JSON-LD)
- Responsive CSS Grid & Flexbox
Contribution areas
- Calculator engine logic and validation
- Regional state & international tax page implementation
- Technical blog posts and formula documentation
- Site performance and mobile layout polish
- SMTP contact & newsletter integration
Editorial contribution
Sameer implements calculator features, regional page templates, and technical documentation. Educational tax copy is reviewed by our SEO editorial lead before publication.
Career architecture
-
Software Developer & Technical Contributor 2023 — Present
Reverse Sales Tax Calculator
I build and maintain the calculator platform—state pages, international VAT/GST tools, India GST hub features, and shared UI components. I implement reverse-tax formulas in JavaScript, optimize page load, and document technical behavior for editorial review.
-
Web Developer 2021 — 2023
Freelance & product teams
Delivered PHP and JavaScript applications for small businesses: booking flows, dashboards, and landing pages with a focus on Core Web Vitals and mobile-first layouts.
-
Junior Web Developer 2020 — 2021
Local agency projects
Started with WordPress and custom PHP sites, then moved into component-based frontends and API-backed forms—foundation work that still shapes how I structure this project.
Academic foundation
Bachelor of Computer Applications (BCA)
Indira Gandhi National Open University (IGNOU)
Experience highlights
- Shipped 100+ regional reverse-tax calculator pages on a single PHP architecture
- Implemented client-side calculators with no server storage of user inputs
- Maintains site-wide glassmorphism UI and dark/light theme system
Credentials
Technical editorial standards
Reverse Sales Tax Calculator — internal QA
View standards →Reverse tax formula documentation
Published on-site technical guide
View formula →Editorial integrity
Calculator logic and technical implementations on this site follow a build-and-review workflow led by Sameer Rayeen:
-
01
Formula implementation
Reverse-tax math uses the standard identity original = total ÷ (1 + rate), implemented with explicit parsing and validation so empty or invalid inputs never silently return misleading numbers.
-
02
Performance & UX checks
Calculators run in the browser; pages are tested on mobile widths, keyboard navigation, and slow connections before release.
-
03
Editorial handoff
Tax rate copy and educational articles are reviewed by our SEO lead before publish—technical accuracy and search quality are separate passes.