Gmail PDF Invoice Extractor with Gemini to Google Sheets

Extract Turkish invoice data from Gmail PDF attachments into Google Sheets—automatically with Gemini

If your invoices arrive by email, this n8n workflow watches your Gmail inbox for PDF attachments, checks whether each PDF is an invoice, and then uses Google Gemini to extract structured invoice headers and line items into Google Sheets—so you can stop manual copy/paste.

What this workflow does

• Runs hourly and triggers on new Gmail messages that match the filter: filename:pdf has:attachment.
• Splits email attachments into individual items and loops through each PDF attachment.
• Uploads each PDF to Google Drive (target Drive folder ID you configure), then downloads it and extracts text from the PDF.
• Uses Google Gemini to determine whether the extracted text is an invoice.
• If it’s not an invoice, the workflow deletes the uploaded file from Google Drive.
• If it is an invoice, Gemini extracts invoice details and line items using a structured JSON schema.
• Appends results to Google Sheets:
  • Invoice headers to the sheet tab “Faturalar”
  • Each invoice line item to the sheet tab “Kalem Detay”

Use cases

• Automate invoice intake for Turkish suppliers that email PDF invoices.
• Maintain up-to-date invoice databases in Google Sheets for accounting review.
• Reduce manual data entry for SaaS operations and internal finance workflows.

Technical details

• n8n scheduling & logic nodes: Runs every hour; uses nodes such as if, set, merge, split out, and sticky note.
• Integrations: Gmail (OAuth2), Google Drive (OAuth2), Google Sheets (OAuth2), and Google Gemini (via Google PaLM/Gemini chat model nodes).
• Setup required: Gmail OAuth2 + query filter, Drive folder ID, Gemini API credentials (for the two Gemini nodes), and your Google Sheets spreadsheet/tab configuration.