{"product_id":"invoice-data-extraction-with-openai-gmail-google-sheets","title":"Invoice Data Extraction with OpenAI, Gmail \u0026 Google Sheets","description":"\u003ch3\u003eExtract invoice data automatically with OpenAI, track it in Google Sheets, and send Gmail alerts\u003c\/h3\u003e\n\u003cp\u003eThis n8n workflow receives invoice uploads via a webhook, uses \u003cstrong\u003eOpenAI\u003c\/strong\u003e to extract structured fields, detects duplicates in \u003cstrong\u003eGoogle Sheets\u003c\/strong\u003e, and sends \u003cstrong\u003eGmail\u003c\/strong\u003e notifications for duplicate or low-confidence invoices—then posts clean invoices to your accounting system via an HTTP request.\u003c\/p\u003e\n\n\u003ch3\u003eWhat this workflow does\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReceives invoice files\u003c\/strong\u003e through a webhook endpoint and validates the uploaded file type.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eExtracts text from PDFs\u003c\/strong\u003e to prepare invoice content for parsing.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eUses OpenAI to extract invoice fields\u003c\/strong\u003e such as vendor, invoice number and dates, totals, currency, and \u003cstrong\u003eline items\u003c\/strong\u003e.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eChecks Google Sheets for duplicates\u003c\/strong\u003e by comparing vendor name and invoice number within the “Invoices” tab.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eValidates line-item totals\u003c\/strong\u003e against the extracted invoice total and flags low-confidence extractions for review.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSends Gmail status emails\u003c\/strong\u003e when duplicates are found or when manual review is needed.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePosts non-flagged invoices\u003c\/strong\u003e to your accounting software using a configurable \u003cstrong\u003eHTTP request\u003c\/strong\u003e, appends the record with status to Google Sheets, and responds to the webhook with a JSON \u003cstrong\u003e“received”\u003c\/strong\u003e message.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRuns daily at 8:00 AM\u003c\/strong\u003e to read the Google Sheets log, filter invoices marked “review,” and email you a reminder list via Gmail.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eUse cases\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eAutomate invoice intake for SaaS operations where invoices arrive as PDF attachments.\u003c\/li\u003e\n  \u003cli\u003ePrevent double-entry by detecting duplicates in an “Invoices” Google Sheets log.\u003c\/li\u003e\n  \u003cli\u003eSpeed up AP review by emailing only duplicates and low-confidence extractions for human validation.\u003c\/li\u003e\n  \u003cli\u003ePush confirmed invoice data to an accounting system through an HTTP endpoint.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical details\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWebhook\u003c\/strong\u003e for file upload intake and JSON “received” responses\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOpenAI\u003c\/strong\u003e for structured invoice extraction\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGoogle Sheets OAuth2\u003c\/strong\u003e to read\/write the “Invoices” tab and track status\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGmail OAuth2\u003c\/strong\u003e for duplicate alerts, review requests, and daily reminders\u003c\/li\u003e\n  \u003cli\u003eWorkflow logic with \u003cstrong\u003eif\u003c\/strong\u003e, \u003cstrong\u003eset\u003c\/strong\u003e, \u003cstrong\u003ecode\u003c\/strong\u003e, plus supporting steps (including sticky notes)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eSetup requires OpenAI, Google Sheets OAuth2, and Gmail OAuth2 credentials, plus configuration of your owner email and the Google Sheets document ID with an “Invoices” tab containing the required columns.\u003c\/p\u003e","brand":"N8N Commerce","offers":[{"title":"Default Title","offer_id":46203575337139,"sku":"N8N-20743","price":2.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0749\/6279\/6723\/files\/A_IDqhDnAGTop1NPQ-PD__f7nqwEQZ.png?v=1791709861","url":"https:\/\/buyflowscripts.com\/products\/invoice-data-extraction-with-openai-gmail-google-sheets","provider":"N8N Commerce","version":"1.0","type":"link"}