n8n Google Sheets + OpenAI Blog Generator Workflow (HTML → Docs)

Generate SEO blog topics and publish-ready HTML articles to Google Docs—directly from your Google Sheets, using OpenAI (GPT-4o) and Anthropic (Claude 4 Sonnet).

This n8n workflow connects Google Sheets, OpenAI, and Anthropic to turn client keywords and instructions into structured content topics for human QC, then converts approved topics into 1500+ word SEO blog posts in plain HTML that are automatically created as Google Docs and linked back to the sheet.

What this workflow does

• Triggers when a client row changes in Google Sheets or on a monthly schedule to start processing clients from the Client Details sheet.
• For each client, uses OpenAI (GPT-4o) to generate a batch of blog title ideas using the client’s keywords, homepage content, competitor URLs, and project instructions.
• Uses OpenAI (GPT-4o) again to review, rewrite, and standardize the title list, then parses results into a structured topic array.
• Writes each topic as a row into the Content Topics tab with the associated Client ID for human QC.
• Runs daily to find Content Topics rows marked QC = Good that don’t yet have a Content URL, then processes topics one by one.
• Loads the matching client details from Google Sheets and uses Anthropic (Claude 4 Sonnet) to generate a 1500+ word SEO article in plain HTML, including the extracted H1.
• Sends the HTML + H1 title to a Google Apps Script web app to create a Google Doc, then updates the Content Topics row with the returned document URL.

Use cases

• SaaS teams who manage multiple clients in Google Sheets and want an automated SEO blog production pipeline with human approval gates.
• Automation engineers building content workflows that create Google Docs from AI-generated HTML and track progress in-sheet.
• Marketing operations that need consistent topic generation, QC, and publishing links per Client ID.

Technical details

• Integrations: Google Sheets, OpenAI (GPT-4o), Anthropic (Claude 4 Sonnet), Google Apps Script (web app).
• n8n flow elements: code, sticky note, HTTP Request, Google Sheets, split in batches, and n8n-nodes-langchainagent.
• Setup: add credentials for Google Sheets, OpenAI, and Anthropic in n8n; replace placeholders like YOUR_GOOGLE_SHEET_ID.