PDFx – Instant PDF/A-3 invoice generation via REST API

Summary: PDFx is a RESTful API that generates compliant PDF/A-3 invoices embedding machine-readable XML in under 100ms. It converts JSON and templates into Factur-X/ZUGFeRD-ready PDFs without storing user data or requiring servers, ensuring privacy and fast performance.

What it does

PDFx uses a custom Lua engine to transform JSON data and templates into PDF/A-3 files with embedded XML for EU e-invoicing compliance. It delivers thousands of PDFs per second with sub-100ms latency and zero dependencies.

Who it's for

Developers needing fast, privacy-focused, and compliant PDF invoice generation, especially for EU electronic invoicing standards.

Why it matters

It solves slow, resource-heavy, and privacy-invasive PDF generation by providing a lightweight, high-performance API that meets EU e-invoicing regulations.