Extract Invoice Data from Slack PDFs to Google Sheets with GPT-4o — n8n Workflow

Medium complexity⚡ Trigger8 nodes🏷️ Invoice Processingby Toshiki Hirao

Overview

Managing invoices manually can be time-consuming and error-prone. This workflow automates the process by extracting key invoice details from PDFs shared in Slack, structuring the information with AI, saving it to Google Sheets, and sending a confirmation back to Slack. It’s a seamless way to keep your financial records organized without manual data entry.

How it works Receive invoice in Slack – When a PDF invoice is uploaded to a designated Slack channel, the workflow is triggered. Fetch the PD

Nodes used

Google SheetsHTTP RequestSlackAI AgentOpenAI Chat ModelStructured Output Parser

Workflow Preview

How it works
1. Receive invoice in Slack – When a PDF invoice is upl
2. Fetch the PDF – The file is downloaded automatically
Workflow
Automate Invoice Extraction from Slack to Google Sheets
Introduction
Managing invoices manually can be time-consuming and er
modelparser
Append row in sheet
Send a message
Structure Output
AI model
⚡
R
Receive invoice pdf
Fetch the pdf
E
Extract information from…
Extract invoice informat…
8 nodes7 edges

How it Works

  1. 1

    Trigger

    The workflow starts with a trigger trigger.

  2. 2

    Process

    Data flows through 8 nodes, connecting agent, extractfromfile, googlesheets.

  3. 3

    Output

    The workflow completes its automation and delivers the result to the configured destination.

Node Details (8)

GO

Google Sheets

googleSheets

#1
HT

HTTP Request

httpRequest

#2
SL

Slack

slack

#3
AI

AI Agent

n8n-nodes-langchain.agent

#4
OP

OpenAI Chat Model

n8n-nodes-langchain.lmChatOpenAi

#5
ST

Structured Output Parser

n8n-nodes-langchain.outputParserStructured

#6

How to Import This Workflow

  1. 1Click Download JSON button on the right to save the workflow file.
  2. 2Open your n8n instance. Go to Workflows → New → Import from file.
  3. 3Select the downloaded extract-invoice-data-from-slack-pdfs-to-google-sheets-with-gpt-4o file and click Import.
  4. 4Set up credentials for each service node (API keys, OAuth, etc.).
  5. 5Click Test Workflow to verify everything works, then activate it.

Or paste directly in n8n → Import from JSON:

{ "name": "Extract Invoice Data from Slack PDFs to Google Sheets with GPT-4o", "nodes": [...], ...}

Integrations

agentextractfromfilegooglesheetshttprequestlmchatopenaioutputparserstructuredslackslacktrigger

Get This Workflow

Download and import in one click

Download JSONView on n8n.io
Nodes8
Complexitymedium
Triggertrigger
CategoryInvoice Processing

Created by

Toshiki Hirao

Toshiki Hirao

@hirao

Tags

agentextractfromfilegooglesheetshttprequestlmchatopenaioutputparserstructuredslackslacktrigger
⚡

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Automate Custom QuickBooks Invoice PDFs & Email with n8n

Standard accounting templates often fail to reflect a premium brand identity. This sophisticated n8n workflow bridges the gap between financial record-keeping and professional client presentation. By moving beyond the native limitations of QuickBooks Online, this automation enables businesses to generate high-end, multi-page PDF invoices that align perfectly with their corporate styling. The process begins the moment a new invoice is generated in QuickBooks, triggering a webhook that captures real-time billing data. The workflow then utilizes advanced HTML-to-File conversion and custom Code nodes to structure data into a polished, branded layout. It handles complex logic such as line-item merging and multi-page formatting automatically. Once the document is rendered, the system bypasses generic 'no-reply' senders by routing the finalized PDF through your preferred email provider. This ensures a seamless, white-labeled experience for your clients while eliminating the manual overhead of exporting, styling, and attaching files. Ideal for agencies and service providers, this flow guarantees that your most frequent touchpoint—the bill—is as professional as your work. **Common Use Cases:** - High-end creative agencies requiring bespoke, white-labeled billing documents for premium clients. - Automated recurring subscription billing where custom tax disclosures or localized branding are required. - Service-based businesses needing to attach dynamic project reports or terms of service directly to QuickBooks invoices.

🔗 Webhook·12 nodes