# QuickBilling — send invoices in minutes; know when they are opened

> QuickBilling helps independents send professional invoices fast and track when clients open them. Invoices and estimates (quotes), secure share links and PDFs, quote-to-invoice conversion, link analytics, expense tracking, team workspaces, and a REST API (OpenAPI).

## Official sites

- Marketing: https://quickbilling.io
- Web app: https://app.quickbilling.io
- API base: https://app.quickbilling.io/api

## Social

- X (Twitter): https://x.com/quickbilling_
- LinkedIn: https://www.linkedin.com/company/112267279
- Instagram: https://www.instagram.com/quickbilling_/

## Product (marketing deep links)

- [Features overview](https://quickbilling.io/features)
- [E-invoicing & estimates](https://quickbilling.io/features/invoicing)
- [Expenses](https://quickbilling.io/features/expenses)
- [Analytics & link tracking](https://quickbilling.io/features/analytics)
- [Templates & branding](https://quickbilling.io/features/templates)
- [Payments roadmap](https://quickbilling.io/features/payments)
- [Custom branding](https://quickbilling.io/features/branding)
- [Security](https://quickbilling.io/features/security)
- [API access](https://quickbilling.io/features/api)
- [Pricing](https://quickbilling.io/pricing)
- [For freelancers & small businesses](https://quickbilling.io/for-freelancers)

## Documentation

- [Help & docs](https://quickbilling.io/docs)
- [Interactive API reference](https://quickbilling.io/docs/api)

## Contact

- Email: info@quickbilling.io

## What QuickBilling is not

- Full general-ledger accounting
- Payroll or payroll taxes
- Merchant of record / payment funds flow (billing is via Stripe subscriptions; payer flows are product-specific)
- Legal or tax advice

## Machine-readable

- [Marketing sitemap](https://quickbilling.io/sitemap.xml) — all public marketing URLs (hreflang en/de/fr/es)
- [App sitemap](https://app.quickbilling.io/sitemap.xml) — public sign-up / pricing / auth help URLs only
- [App llms.txt](https://app.quickbilling.io/llms.txt) — signed-in product route index for assistants
- [OpenAPI (marketing mirror)](https://quickbilling.io/openapi.yaml)
- [OpenAPI (app /api proxy)](https://app.quickbilling.io/api/openapi.yaml)
- [Marketing robots](https://quickbilling.io/robots.txt) · [App robots](https://app.quickbilling.io/robots.txt)