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Possible SetupFinance & Invoicing

AI-Powered Invoice Data Extraction

OCR plus AI reads invoice numbers, line items and tax rates from any format, catches duplicates and posts to SAP. Demo, figures modelled.

Industry
Finance & Accounting
Build, estimated
6 weeks

At a glance

It starts with
Invoice Received
The machine handles
11 of 12 steps
A person keeps
Manual Review
Bottom line
-85%Processing Time

The problem

Open a PDF invoice and find the invoice number — takes you two seconds. A computer in the nineties would have failed at it.

Today, the same thing costs one AI API call and lands at 95 to 99 percent accuracy. Even when the supplier writes "Ref no." instead of "Invoice number". Even when the invoice is a crooked phone photo.

So the question is no longer whether this works. It's why three people in your company spend every day transferring the same five fields into SAP — at 500 invoices a month, that's 33 hours of typing per week.

This showcase walks the full route from "PDF in the inbox" to "posted in SAP" — with duplicate blocking, plausibility checks, and a human only where the AI is uncertain.

Invoice processing consumes significant resources in many organizations. Typical scenario: Monthly, over 500 invoices from more than 200 suppliers arrive via email, mail, and fax. Three full-time employees spend their workdays transferring data from PDFs, scanned documents, and images manually into SAP. Invoices come in wildly different formats: invoice numbers positioned top left on some, bottom right on others, various languages. Every wrong number means reconciliation problems at month-end. Error rates hover around 8% - leading to duplicate payments, missed early payment discounts, and frustrated suppliers. Average processing time per invoice is 4 minutes, adding up to 33 hours of pure data entry per week. Audits are problematic since traceability is lacking. Annual costs for late fees and missed discounts easily exceed €50,000. The monotonous work leads to high department turnover.

The process, step by step

Scroll through. The diagram stays put and highlights the step you are on.

The workflow01 / 12
  1. 01

    Invoice Received

    Email / Upload

    A new invoice is received via email or manually uploaded, triggering the automation process.

  2. 02

    OCR Extraction

    Google Cloud Vision

    Google Cloud Vision OCR analyzes the PDF/image and extracts all relevant data: vendor, invoice number, date, line items, amounts.

  3. 03

    AI Validation

    OpenAI GPT-4

    OpenAI GPT-4 validates the extracted data against business rules and historical patterns. Inconsistencies are detected.

  4. 04

    Duplicate Check

    PostgreSQL

    The system checks the PostgreSQL database to see if this invoice already exists, preventing duplicate payments.

  5. 05Branch

    Duplicate?

    Gateway decision: Was a duplicate found? If yes, the process is aborted and the invoice is rejected.

  6. 06

    Duplicate Rejected

    Already Exists

    The invoice was identified as a duplicate and is automatically rejected. The process ends here.

  7. 07Branch

    Valid?

    Gateway decision: Is all data complete and valid? If no, the invoice is routed for manual review.

  8. 08Human decides

    Manual Review

    Error Detected

    An employee manually reviews and corrects the invoice. After correction, it's sent through AI validation again.

  9. 09

    Auto-Categorization

    AI Cost Center Assignment

    AI automatically categorizes the invoice and assigns it to the correct cost center based on historical data.

  10. 10

    SAP Integration

    Data to ERP

    The validated and categorized invoice data is automatically transferred to SAP and stored in the ERP system.

  11. 11

    Notification

    Team Informed

    The accounting team receives a notification about the successfully processed invoice with all relevant details.

  12. 12

    Complete

    Invoice Processed

    The invoice is fully processed, stored in the system, and ready for payment approval.

What changes

Possible setup, not a packaged product

The figures are modelled target values for a possible setup, derived from industry benchmarks and our own tests. They do not come from a customer project; real values depend on your business. We do not sell this setup as a finished product: we measure where your bottleneck is, then build with your team. For systems that require certification (e.g. HIS, gematik, DATEV-certified) we work with specialised partners.

Before vs. After

AspectBeforeAfter
Data EntryBefore: Manual data entry from PDF invoicesAfter: Automatic OCR extraction with AI validation
Processing TimeBefore: 15-20 minutes per invoiceAfter: 2-3 minutes end-to-end
Error RateBefore: Up to 8% in data entryAfter: Below 0.5%
Duplicate DetectionBefore: No automatic detectionAfter: Intelligent duplicate detection

Technology

Technology Stack

n8nGoogle Cloud VisionOpenAI GPT-4PostgreSQLSAP Integration

Integrations

Systems this setup can connect to

SAP S/4HANAERP System
Direct integration via SAP BTP API for invoice booking and cost center assignment
Google Cloud VisionOCR Engine
State-of-the-art OCR technology for reliable text recognition from any document
OpenAI GPT-4AI Validation
Intelligent validation and categorization of invoice data
PostgreSQLDatabase
High-performance database for duplicate detection and data storage

Frequently Asked Questions

The system processes PDF invoices, scanned documents, and images. Google Cloud Vision OCR reliably recognizes text from practically all formats, including ZUGFeRD and XRechnung.
With the combination of Google Cloud Vision and GPT-4 validation, we achieve an extraction accuracy of over 99%. AI validates the extracted data against business rules and detects inconsistencies.
The system uses the SAP Business Technology Platform API to transfer validated invoice data directly into the ERP system. All cost centers and G/L accounts are automatically assigned.
Yes, an intelligent duplicate detection checks every invoice against existing entries. Based on invoice number, amount, vendor, and date, duplicates are reliably identified and rejected.