One-Time Source Code Sale · Full IP & Ownership

Own a production-ready scientific calculator product.

NexusCalc v3.1 is a complete, high-quality, ready-to-sell scientific computing platform — Desktop app (Windows · macOS · Linux) and a fully offline Mobile PWA in one package.

· Desktop App· Mobile PWA· Full Source Code· Commercial License
ULTRA CALC v3.1
2(3 + 4) · sin(π/6)
= 7.0000
sin
cos
tan
ln
log
7
8
9
÷
4
5
6
×
1
2
3
π
0
.
ans
+
=
History
Memory · 10
Export
Two products in one

One package. Two platforms.

A fully native-feeling desktop application and a complete mobile Progressive Web App — both production-grade, both yours.

Desktop Application

Native-quality desktop app for Windows, macOS and Linux. Custom interface, smooth animations, full keyboard support and shortcuts.

  • Pre-compiled .exe and .app included
  • Dark & light themes
  • Works fully offline

Mobile PWA

100% offline after first visit. Installable on iOS and Android. Full feature parity with the desktop version — Service Worker + PWA Manifest baked in.

  • Add to Home Screen on any device
  • Offline-first architecture
  • No app store required
ULTRA CALC v3.1 Engine

Built on a serious computation core.

Everything you need to ship a credible, professional-grade calculator product.

Advanced Expression Parser

Implicit multiplication (2(3+4)), variables, custom functions, and ans. Natural math input that just works.

SymPy + Secure AST

Symbolic math powered by SymPy with a hardened AST fallback — no eval, no pickle, no surprises.

37 Math & Stats Operations

From trig and logarithms to statistics and matrices — a complete computational toolkit.

Unit Converter · 17 Categories

Length, mass, time, energy, temperature, currency and more — professional-grade conversion.

Financial Calculator

Compound interest, loans, ROI, break-even, tip — built for real-world use cases.

History · Memory · Export

Full history, 10 memory slots, and exports to JSON, CSV, LaTeX and Excel.

Export to JSON · CSV · LaTeX · Excel
89
Unit Tests
37
Operations
17
Unit Categories
10
Memory Slots
100%
Offline
Package contents

What's inside the box.

Everything you need to ship under your own brand from day one.

  • Complete source code — Desktop, Mobile and Core Engine
  • Full Intellectual Property Rights — the code becomes 100% yours
  • All assets, icons, screenshots and documentation
  • Pre-compiled executables (.exe and .app)
  • Commercial license — modify, rebrand and resell compiled products
  • 89 comprehensive unit tests
  • Plugin system for easy extensions
  • Secure JSON-based session system (no pickle vulnerabilities)
  • Detailed documentation and buyer's guide
Ideal for

Who this is for.

If you're serious about shipping a real product, NexusCalc gives you a head start measured in months.

Launch your own calculator

Rebrand, white-label and sell as your own product.

Foundation for a bigger product

Use as the math core for an education or science platform.

Portfolio expansion

Add a polished, premium product to your software portfolio.

Premium desktop + mobile tool

Offer high-value internal tooling to teams and clients.

One-time purchase

Own it. Forever.

No subscriptions. No royalties. A single payment and the product is yours.

NexusCalc v3.1 — Full Package
$599one-time

Open to slight negotiation

Full source code · Commercial license · Lifetime ownership

  • Complete source code (Desktop + Mobile + Core)
  • Full Intellectual Property & ownership
  • Pre-compiled .exe and .app
  • Commercial license to rebrand & resell compiled
  • All assets, icons and documentation
  • Lifetime ownership — no recurring fees

Serious buyers only · Chat-only communication · No calls / Zoom / meetings

Sale terms

Clear, simple, one-time.

Full transparency on what you can and can't do after purchase.

You can

  • Modify and customize the code
  • Rebrand and white-label the product
  • Embed in other software you build
  • Sell the compiled software under your brand
  • Use commercially with no royalties

You cannot

  • Reselling the raw source code as-is
  • Claiming authorship of the original engine
FAQ

Common questions.

Anything else? Reach out via chat after purchase.

Launch your own premium calculator product today.

NexusCalc v3.1 — engineered for excellence. Owned by you after purchase.