About this product

THE OUTCOME

Open one file and invoice like a pro: your business details auto-fill, line items total themselves live, discounts and taxes compute correctly to the cent, and the result prints to a clean PDF in three professional themes. Saved invoices, duplicate-for-repeat-clients, one-click "mark paid," and automatic overdue flags keep your money organized.

WHO IT IS FOR

• Freelancers and solopreneurs who invoice clients regularly
• Small businesses tired of subscription invoicing tools
• Anyone who wants invoices that live on their own computer, not in someone else's cloud

THE PROBLEM

Invoicing software wants a monthly subscription for the privilege of sending your own bills. The alternative is rebuilding invoices in Word every time — no running totals, no saved clients, no idea what's overdue. For a freelancer or small business sending a handful of invoices a month, both options are bad deals.

THE SOLUTION

One self-contained file you own forever — no subscription, no account, no server, works offline. Your business profile auto-fills; line items, discounts (percent or flat), two configurable taxes, and balance-due compute live to the cent; you pick one of 3 professional themes and print to PDF. A saved-invoice manager tracks statuses, duplicates repeat invoices, and flags what's overdue.

WHAT'S INCLUDED (exact files)

• InvoiceForge.html — the complete invoicing app in ONE self-contained file. Zero external requests; works offline in any modern browser.
• Invoice editor: business profile auto-fill, client fields, auto-incrementing invoice numbers with editable prefix, issue/due dates with Net 7/14/30/60 quick terms, 6 currencies (USD, EUR, GBP, CAD, AUD, JPY) with correct formatting everywhere
• Line items: description, quantity, rate, auto amounts; add, remove, and reorder rows
• Live totals: subtotal, percent OR flat discount, two configurable taxes (applied to the discounted subtotal), shipping/flat fee, total, amount paid, balance due — all rounded to cents
• 3 one-click invoice themes: Modern, Classic, Minimal — the preview updates live in an A4-proportioned render
• Print / Save as PDF via the browser print dialog with a dedicated invoice-only stylesheet (no app chrome in the output)
• Saved-invoice manager: save, list, search, duplicate, delete, mark paid; summary bar with outstanding balance and overdue count; statuses (Draft / Sent / Paid / Overdue) update automatically
• Sample invoice preloaded (fictional) with Load sample / Clear controls; business profile saved in-browser
• Backup: export/import everything as JSON
• Quick-Start-Guide.pdf — your first invoice in 5 minutes, themes and printing, managing saved invoices, the backup habit, an honest list of what the app does NOT do, and FAQ
• README-license.txt — contents, formats, license, support

HOW IT WORKS

Download the ZIP → double-click InvoiceForge.html → fill in your business profile once → create an invoice (or load the sample to explore) → pick a theme → Print / Save as PDF → send the PDF to your client however you like.

IDEAL CUSTOMER

You're a freelancer or solopreneur (or a small business owner) who sends a handful of invoices a month and is tired of either paying a monthly fee for billing software or rebuilding invoices in Word. You want professional-looking invoices in minutes, correctly computed, that live on your own computer. You'll send the PDF yourself, collect payment your usual way, and export a backup regularly.

WHO IT IS NOT FOR

• Businesses that need payment processing — the app creates invoices; it does not charge credit cards or move money (you send the PDF and get paid your usual way)
• Buyers who want automated email sending, recurring-invoice automation, or multi-device sync — this is a single-user offline tool; you'll attach PDFs to your own emails and keep backups yourself
• Anyone who needs full accounting software — InvoiceForge is an invoicing tool, not accounting, tax, or legal software (verify tax treatment for your jurisdiction with a qualified professional)

REQUIREMENTS & LIMITATIONS

• None — if you can use a web form, you can use InvoiceForge.
• The app: any modern browser — Chrome, Edge, Safari, Firefox — desktop or mobile; works offline
• Guides: PDF, any reader
• No payment processing: the app creates invoices; it does not charge credit cards or move money. You send the PDF and get paid your usual way.
• No automatic email sending: you attach the PDF to your own email or messages.
• Data lives in your browser's localStorage on one device: use the built-in Export backup regularly; clearing browser data erases local data unless exported. It does not sync between devices.
• Single-user tool; no multi-user or team features in v1.
• Invoice numbers auto-increment from a counter; gaps can occur if you start an invoice without saving it.
• This is an invoicing tool, not accounting, tax, or legal software. Verify tax treatment for your jurisdiction with a qualified professional.

FAQ

• Do I need the internet? No. The file has zero external dependencies and works fully offline once saved on your computer.
• Where is my data stored? Privately in your browser's localStorage. Nothing is uploaded to any server. Export backups from the Backup tab.
• Can I use it on my phone? Yes — it runs in any modern mobile browser and the layout is responsive.
• How do taxes work? Two configurable tax rates, both applied to the discounted subtotal (the standard treatment). Rename the labels to match your jurisdiction.
• Can I add my logo image? v1 shows your logo text from your business profile; image-logo upload is not included. The printed invoice still looks clean and professional.

SUPPORT & UPDATES

Questions? Contact me through this Gumroad product page. Instant download as a ZIP (InvoiceForge-v1/); yours to keep; free updates to v1.x.

What's included

• InvoiceForge App (single HTML file) — the complete invoicing app in ONE self-contained file. Zero external requests; works offline in any modern browser.
• Invoice editor: business profile auto-fill, client fields, auto-incrementing invoice numbers with editable prefix, issue/due dates with Net 7/14/30/60 quick terms, 6 currencies (USD, EUR, GBP, CAD, AUD, JPY) with correct formatting everywhere
• Line items: description, quantity, rate, auto amounts; add, remove, and reorder rows
• Live totals: subtotal, percent OR flat discount, two configurable taxes (applied to the discounted subtotal), shipping/flat fee, total, amount paid, balance due — all rounded to cents
• 3 one-click invoice themes: Modern, Classic, Minimal — the preview updates live in an A4-proportioned render
• Print / Save as PDF via the browser print dialog with a dedicated invoice-only stylesheet (no app chrome in the output)
• Saved-invoice manager: save, list, search, duplicate, delete, mark paid; summary bar with outstanding balance and overdue count; statuses (Draft / Sent / Paid / Overdue) update automatically
• Sample invoice preloaded (fictional) with Load sample / Clear controls; business profile saved in-browser
• Backup: export/import everything as JSON
• Quick-Start Guide (PDF) — your first invoice in 5 minutes, themes and printing, managing saved invoices, the backup habit, an honest list of what the app does NOT do, and FAQ
• README & license file

Key features

• Every calculation tested: 63 automated checks covering multi-item totals, percent vs flat discounts, dual taxes on the discounted subtotal, partial-payment balances, currency switching, auto-numbering, and overdue logic — zero failures — so your invoices are always correct to the cent
• No macros, no plugins, no account, no server — one HTML file you own forever — so there's no subscription, no login, and no one else's cloud holding your billing data
• Your data stays in your browser (localStorage); nothing uploads anywhere — so your client list and invoices never leave your computer