Pro Invoice & Estimate Maker
LiveOffline invoice and estimate generator for small businesses. Create professional invoices with customizable templates, export/import as JSON, toggle dark mode, and print-to-PDF. Single-file app that runs entirely in your browser.
What It Does
- →Generate invoices and estimates with line items, tax, discounts, and totals
- →Customizable business details and invoice templates
- →Export data as JSON for backup or sharing across devices
- →Print-to-PDF using browser native print dialog
- →Works offline - no server required, everything stays in your browser
What I Built
- →Single-page React app with localStorage persistence
- →Dynamic form state management for line items and calculations
- →JSON import/export for data portability
- →CSS print styles optimized for PDF generation
- →Dark mode toggle with theme persistence
Who It's For
Freelancers & Contractors
Generate professional invoices without paying for QuickBooks or FreshBooks. Keep your data local, export backups as JSON, and print to PDF for client emails.
Service Businesses
Create estimates on-site with a laptop or tablet. No internet required. Print directly or save as PDF to send later.
Privacy-Conscious Users
All data stays in your browser. No cloud sync, no accounts, no tracking. Export your invoices as JSON files and keep them wherever you want.
Technical Approach
Offline-first architecture: Built as a single-page app with no backend. All invoice data is stored in browser localStorage, making it instantly available even without internet.
JSON portability: Export button generates a JSON file containing all your invoices, templates, and business info. Import it on another device or keep it as a backup.
Print optimization: Custom CSS print styles format invoices for PDF generation. Uses browser's native print dialog—no third-party PDF libraries or server-side rendering.
State management: React state handles dynamic line items, automatic subtotal/tax/total calculations, and instant preview updates.