{"product_id":"n8n-inventory-reorder-automation-google-sheets-gmail-gpt-4-mini","title":"n8n Inventory Reorder Automation: Google Sheets + Gmail + GPT-4 Mini","description":"\u003ch3\u003eAuto-reorder inventory from Google Sheets—with Gmail approvals and GPT-4 Mini order confirmation\u003c\/h3\u003e\n\u003cp\u003eThis n8n workflow audits your inventory and open purchase orders in Google Sheets, calculates what to reorder using measured demand and lead times, and then emails purchase orders to suppliers via Gmail—optionally requesting buyer approval and extracting confirmed quantities from supplier replies with OpenAI (GPT-4 Mini).\u003c\/p\u003e\n\n\u003ch3\u003eWhat this workflow does\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRuns every weekday morning\u003c\/strong\u003e on a schedule to start a replenishment run and keep your reorder cycle on track.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReads multiple Google Sheets tabs\u003c\/strong\u003e (Products, Stockouts, Sales, Purchase orders, Suppliers, and Reorder log) to audit inventory health and purchase order status.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlags issues\u003c\/strong\u003e such as late deliveries, short receipts, and stock records that don’t reconcile—then logs follow-up actions back to the \u003cem\u003eReorder log\u003c\/em\u003e.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eChases overdue\/short deliveries\u003c\/strong\u003e by emailing suppliers and notifies operations to investigate stock discrepancies (all via Gmail).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCalculates reorder quantities\u003c\/strong\u003e by measuring demand while excluding stockout days and sales spikes, and determines supplier lead times from receipt history (or falls back to quoted lead time when history is thin).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBuilds one proposed purchase order per supplier\u003c\/strong\u003e, and routes it to: send immediately, hold for a later run, or request buyer approval by email.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTracks orders for execution\u003c\/strong\u003e: when an order is sent, it emails the supplier the purchase order and writes each order line into the \u003cem\u003ePurchase orders\u003c\/em\u003e tab.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReconciles supplier responses\u003c\/strong\u003e: polls Gmail for new replies and uses \u003cstrong\u003eOpenAI (GPT-4 Mini)\u003c\/strong\u003e to extract confirmed quantities\/dates\/prices from \u003cem\u003ethe new reply text only\u003c\/em\u003e, then updates the order pipeline.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eUse cases\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eWeekly replenishment runs that reduce stockouts by automatically scheduling reorder emails and logging outcomes.\u003c\/li\u003e\n  \u003cli\u003eSupplier follow-ups for overdue or short deliveries, with an auditable history in Google Sheets.\u003c\/li\u003e\n  \u003cli\u003eCleaner procurement operations by turning email confirmations into structured updates using GPT-4 Mini.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical details\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGoogle Sheets\u003c\/strong\u003e (Products, Stockouts, Sales, Purchase orders, Suppliers, Reorder log)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGmail\u003c\/strong\u003e (supplier chase emails, buyer approval requests, purchase order sending, reply polling)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOpenAI (GPT-4 Mini)\u003c\/strong\u003e (extracts confirmed quantities\/dates\/prices from new supplier reply text)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003en8n nodes\/stacks\u003c\/strong\u003e: if, set, code, no op, gmail, switch\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"N8N Commerce","offers":[{"title":"Default Title","offer_id":46081413382323,"sku":"N8N-19878","price":67.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0749\/6279\/6723\/files\/5lMTHaQeGuiAMsTFgxJdH_vftrudnC.png?v=1790240904","url":"https:\/\/buyflowscripts.com\/products\/n8n-inventory-reorder-automation-google-sheets-gmail-gpt-4-mini","provider":"N8N Commerce","version":"1.0","type":"link"}