n8n WhatsApp Proposal Generator: Voice/Text to PDF with GPT

Turn WhatsApp messages into instant, personalized PDF proposals—using n8n + GPT

This n8n WhatsApp Proposal Generator converts a prospect’s WhatsApp voice or text into a clean, branded PDF proposal in minutes. It transcribes the message, extracts key details with Whisper and GPT, selects the best matching service pack from Airtable, and returns the final PDF to the user instantly via WhatsApp or email.

What this workflow does

• Receives WhatsApp input (voice or text) and transcribes it using Whisper or processes it with GPT.
• Extracts key information with AI (name, need, context, urgency).
• Matches the most relevant service pack by comparing the prospect’s needs against your Airtable service pack records.
• Dynamically fills a branded proposal template using APITEMPLATE (HTML or PDF) with placeholders like {{nom}}, {{prix}}, and {{lien_reservation}}.
• Generates a complete proposal PDF including dynamic links (e.g., payment and calendar links stored with each service pack).
• Sends the PDF instantly back to the prospect via WhatsApp or email.

Use cases

• Book more calls: prospects text a request, get a proposal with a reservation link automatically.
• Sales automation for service businesses: receive voice notes, return structured offers in PDF format.
• Faster quoting: convert “what do you offer and how much?” messages into tailored proposals without manual effort.

Technical details

• Estimated setup time: 45–60 minutes.
• Requirements: WhatsApp Business Cloud API (webhook configured), OpenAI API key (Whisper + GPT), Airtable (service packs + client input), APITEMPLATE (template with placeholders), and an n8n instance (cloud or self-hosted).
• Workflow nodes/stack includes: set, switch, split out, WhatsApp, sticky note, HTTP Request.