Validate email hero images with Gmail, Dropbox, OCR.Space and Google Sheets

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1. Workflow Overview

How it works Expected Image Download The expected image’s Dropbox URL is passed directly into an HTTP Request node, which downloads the image as binary data. Actual Image Extraction The HTML node e...

Best for

Document Extraction automation workflows
AI Summarization automation workflows
intermediate n8n builders looking for reusable templates

Tools used

n8n-nodes-base.manualtrigger, n8n-nodes-base.gmail, n8n-nodes-base.code, n8n-nodes-base.httprequest, n8n-nodes-base.merge, n8n-nodes-base.stickynote, n8n-nodes-base.googlesheets

Source and attribution

This workflow is cataloged by N8N Workflows and links back to its original n8n.io source page by Sasikala Jayamani.

Original n8n.io source

1.1 Workflow description

Title: Validate email hero images with Gmail, Dropbox, OCR.Space and Google Sheets
Workflow name: Validate email hero images with Gmail, Dropbox, OCR.Space and Google Sheets

How it works

Expected Image Download The expected image’s Dropbox URL is passed directly into an HTTP Request node, which downloads the image as binary data.

Actual Image Extraction The HTML node extracts the src of the image from the email (e.g., hero image or other targeted image sections). This src is passed into another HTTP node to download the actual email image in binary format.

OCR Processing Both binary images are sent separately to OCR.Space API via POST requests. OCR returns extracted text for each image.

Comparison A JS node compares the Expected Image Text vs Actual Image Text. If the texts match, the result is marked Match; otherwise Mismatch.

Write Back to Google Sheets The workflow writes ExpectedText, ActualText, and Result back into the Google Sheet, creating a clear audit trail for validation.

Setup steps

1. Google Sheets Create a sheet with the following columns:

SectionId ExpectedImageURL ExpectedText ActualText (output) Result (output)

Add the expected text that should appear inside each image.

2. Email HTML Source Use one of the following:

Gmail node — fetches the email HTML via unread or filtered messages HTTP Request / binary file input — if HTML is being pulled from storage or a URL Ensure the HTML extraction node can find the image src correctly

3. Expected Image (Dropbox URL)

Paste the public Dropbox URL directly into the Google Sheet This URL is fed into an HTTP Download node The resulting binary is used for OCR extraction

4. OCR Setup

Add your OCR.Space API key in the HTTP POST node Set the request body to include:

apikey the binary property of the image desired OCR settings (language, text extraction mode)

5. Merge & Compare

Use a Merge node to align:

ExpectedImageURL + ExpectedText ActualImageSrc OCR outputs

6. In the Code node:

Normalize both texts Compare and assign Match or Mismatch

7. Write Output Use a Google Sheets Append/Update node to write:

ActualText Result

back into the corresponding row, using SectionId or ExpectedImageURL as the matching key.

1.2 Logical Blocks

This catalog entry is organized from the workflow JSON. The node-level section below shows the executable blocks available for review before importing the template.

2. Block-by-Block Analysis

Block 1 - When clicking ‘Execute workflow’

Type / Role: n8n-nodes-base.manualTrigger - manualTrigger
Config choices: Version 1

Block 2 - Get many messages

Type / Role: n8n-nodes-base.gmail - gmail
Config choices: Version 2.2

Block 3 - Extract Hero Image SRC From HTML

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 4 - Convert Image File from HTML to Binary

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.3

Block 5 - Convert Image File from Dropbox to Binary

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.3

Block 6 - Combine Image Outputs

Type / Role: n8n-nodes-base.merge - merge
Config choices: Version 3.2

Block 7 - Extract Content Match Results

Type / Role: n8n-nodes-base.code - code
Config choices: Version 2

Block 8 - Sticky Note

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 9 - Sticky Note4

Type / Role: n8n-nodes-base.stickyNote - stickyNote
Config choices: Version 1

Block 10 - Log Image Checks to Excel

Type / Role: n8n-nodes-base.googleSheets - googleSheets
Config choices: Version 4.7

Block 11 - Extracting Expected Image Content from OCR1

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.3

Block 12 - Extracting Actual Image Content from OCR

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.3

3. Summary Table

Workflow	Validate email hero images with Gmail, Dropbox, OCR.Space and Google Sheets
Complexity	intermediate
Nodes	12
Categories	Document Extraction, AI Summarization
Author	Sasikala Jayamani
Published	25 Feb 2026

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

Use the JSON export at /data/workflows/13679/13679.json as the source template for this automation.
2. Import the template into n8n

Open n8n, import the downloaded JSON, and review each node before activating the workflow.
3. Configure credentials and variables

Replace placeholder credentials, API keys, webhook URLs, account IDs, and environment-specific values with your own settings.
4. Test with sample data

Run the workflow manually or in a staging workspace, inspect node output, and confirm downstream systems receive the expected data.
5. Activate and monitor

Enable the workflow only after testing, then monitor executions, errors, and rate limits during the first production runs.

5. General Notes & Resources

Review imported nodes carefully before activation. This catalog entry is intended to help you inspect the workflow structure, understand required services, and find related templates faster.

Node names, credentials, schedules, webhook paths, and external service limits may need adjustment for your workspace.

Download workflow JSON Original n8n.io source Document Extraction workflows AI Summarization workflows

Frequently asked questions

What does Validate email hero images with Gmail, Dropbox, OCR.Space and Google Sheets do?

What do I need before importing this workflow?

Review the workflow JSON, configure any required credentials in n8n, and test the automation in a safe workspace before using it in production.

Can I customize this workflow?

Yes. Use the block-by-block analysis and the downloadable JSON to inspect each node, then adjust credentials, prompts, schedules, filters, or destinations for your Document Extraction, AI Summarization use case.

Sasikala Jayamani

3 workflows

Nodes

n8n-nodes-base.manualtrigger n8n-nodes-base.gmail n8n-nodes-base.code n8n-nodes-base.httprequest n8n-nodes-base.merge n8n-nodes-base.stickynote n8n-nodes-base.googlesheets

Complexity

intermediate

Published 25 Feb 2026

Likes 0

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Install path: /data/workflows/13679/13679.json

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Validate email hero images with Gmail, Dropbox, OCR.Space and Google Sheets

Workflow preview

1. Workflow Overview

Best for

Tools used

Source and attribution

1.1 Workflow description

How it works

Setup steps

1.2 Logical Blocks

2. Block-by-Block Analysis

Block 1 - When clicking ‘Execute workflow’

Block 2 - Get many messages

Block 3 - Extract Hero Image SRC From HTML

Block 4 - Convert Image File from HTML to Binary

Block 5 - Convert Image File from Dropbox to Binary

Block 6 - Combine Image Outputs

Block 7 - Extract Content Match Results

Block 8 - Sticky Note

Block 9 - Sticky Note4

Block 10 - Log Image Checks to Excel

Block 11 - Extracting Expected Image Content from OCR1

Block 12 - Extracting Actual Image Content from OCR

3. Summary Table

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

2. Import the template into n8n

3. Configure credentials and variables

4. Test with sample data

5. Activate and monitor

5. General Notes & Resources

Frequently asked questions