Best E-Invoicing Solutions for n8n

Coretool is an online invoicing platform designed specifically for freelancers, sole traders, tradespeople, small service businesses, and other enterprises in Germany. With this application, users can generate and oversee quotes and invoices, including compliance with XRechnung and ZUGFeRD e-invoicing standards, manage customer relationships, issue payment reminders, and schedule appointments. The software integrates GiroCode QR codes, facilitates digital signatures for quotes, and enables e-invoice document validation through its REST API. By utilizing API-based workflows, users can link Coretool with automation platforms like Make, Zapier, and n8n, though access to certain specialized modules may require approval. Additionally, it allows users to incorporate calendar feeds into Google, Apple, or Outlook calendars. An optional Kalkulations-Assistent feature aids in estimating projects, calculating materials and labor, and producing quotes. Coretool operates entirely within a web browser, eliminating the need for any local software installation. The free plan permits the issuance of three invoices each month, while the Solo plan is available for €9 per month plus VAT and offers the flexibility of monthly cancellation. Furthermore, the intuitive interface makes it easy for users to navigate through the various functionalities and enhance their invoicing experience.

Rechnungswandler.de serves as an online e-invoicing solution tailored for freelancers and small enterprises in Germany. This platform facilitates the transformation of invoice data input through a form or extracted from various file types, such as PDF, Word, Excel, and scanned documents, into compliant XRechnung or ZUGFeRD formats based on EN 16931 standards. Users have the ability to review the extracted data and download the finalized invoice, while a viewer tool allows for the examination of incoming e-invoices. Since both the conversion and viewing processes occur locally within the browser, users' invoice files remain secure and are not uploaded during these tasks. The platform offers premium features that include the preservation of the original document layout, the capability for batch conversions, storing customer information, utilizing reusable templates, sending payment reminders, and generating validation reports. Additionally, an optional AI feature can assist by recommending any missing information. Users have the flexibility to create new invoices via the web form or modify existing documents, all without the need for desktop software installation. A free tier with certain usage restrictions is available, alongside paid plans that can be purchased for 24-hour access, monthly subscriptions, or annual memberships. Overall, Rechnungswandler.de combines convenience, security, and advanced features to streamline the invoicing process for its users.

InvoiceXML serves as an API-centric platform tailored for achieving e-invoice compliance across Europe. Its REST API is capable of generating, validating, and converting a wide array of formats that fall under EN 16931, including Factur-X, ZUGFeRD, XRechnung, UBL, and CII. The generation process takes in clean JSON data and produces either a compliant XML document or a PDF/A-3 hybrid invoice, complete with embedded XML following specific formatting guidelines. Validation is conducted using the official Schematron rulesets, which not only deliver structured results but also provide accessible explanations in plain language alongside the raw outputs of the rules. For format conversion, the API endpoint (POST /v1/convert/{from}/to/{format}) allows the transformation of any supported format into another via a unified internal representation. Additionally, a dedicated namespace, /v1/transform/, facilitates AI-driven extraction from older PDF invoices into organized XML. Moreover, No-Code integrations enable users without programming skills to access core functionalities seamlessly. The MCP server supplies a robust compliance toolkit designed for AI-assisted workflows, ensuring that the platform is consistently aligned with the latest standards, requiring no ongoing maintenance for users. This approach not only simplifies the compliance process but also enhances efficiency for businesses navigating the e-invoicing landscape.