Process large documents with OCR using SubworkflowAI and Gemini

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Important notice

This workflow is provided as-is. Please review and test before using in production.

1. Workflow Overview

Working with Large Documents In Your VLM OCR Workflow Document workflows are popular ways to use AI but what happens when your document is too large for your app or your AI to handle? Whether its c...

Best for

Document Extraction automation workflows
Multimodal AI automation workflows
advanced n8n builders looking for reusable templates

Tools used

n8n-nodes-base.wait, n8n-nodes-base.httprequest, n8n-nodes-base.manualtrigger, n8n-nodes-base.googledrive, n8n-nodes-base.splitout, n8n-nodes-base.stickynote, n8n-nodes-base.if, @n8n/n8n-nodes-langchain.googlegemini

Source and attribution

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

Original n8n.io source

1.1 Workflow description

Title: Process large documents with OCR using SubworkflowAI and Gemini
Workflow name: Process large documents with OCR using SubworkflowAI and Gemini

Working with Large Documents In Your VLM OCR Workflow

Document workflows are popular ways to use AI but what happens when your document is too large for your app or your AI to handle? Whether its context window or application memory that's grinding to a halt, Subworkflow.ai is one approach to keep you going.

> Subworkflow.ai is a third party API service to help AI developers work with documents too large for context windows and runtime memory.

Prequisites

You'll need a Subworkflow.ai API key to use the Subworkflow.ai service.
Add the API key as a header auth credential. More details in the official docs https://docs.subworkflow.ai/category/api-reference

How it Works

Import your document into your n8n workflow
Upload it to the Subworkflow.ai service via the Extract API using the HTTP node. This endpoint takes files up to 100mb.
Once uploaded, this will trigger an Extract job on the service's side and the response is a "job" record to track progress.
Poll Subworkflow.ai's Jobs endpoint and keep polling until the job is finished. You can use the "IF" node looping back unto itself to achieve this in n8n.
Once the job is done, the Dataset of the uploaded document is ready for retrieval. Use the Datasets and DatasetItems API to retrieve whatever you need to complete your AI task.
In this example, all pages are retrieved and run through a multimodal LLM to parse into markdown. A well-known process when parsing data tables or graphics are required.

How to use

Integrate Subworkflow's Extract API seemlessly into your existing document workflows to support larger documents from 100mb+ to up to 5000 pages.

Customising the workflow

Sometimes you don't want the entire document back especially if the document is quite large (think 500+ pages!), instead, use query parameters on the DatasetItems API to pick individual pages or a range of pages to reduce the load.

Need Help?

Official API documentation: https://docs.subworkflow.ai/category/api-reference
Join the discord: https://discord.gg/RCHeCPJnYw

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 - Wait

Type / Role: n8n-nodes-base.wait - wait
Config choices: Version 1.1

Block 2 - Check Job Status

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.2

Block 3 - Get Dataset Items

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.2

Block 4 - Get Dataset

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.2

Block 5 - When clicking ‘Execute workflow’

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

Block 6 - Download file

Type / Role: n8n-nodes-base.googleDrive - googleDrive
Config choices: Version 3

Block 7 - Split Out

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

Block 8 - Sticky Note

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

Block 9 - Extract API

Type / Role: n8n-nodes-base.httpRequest - httpRequest
Config choices: Version 4.2

Block 10 - Sticky Note1

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

Block 11 - Sticky Note2

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

Block 12 - Sticky Note4

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

Block 13 - Job Complete?

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

Block 14 - Document OCR via VLM

Type / Role: @n8n/n8n-nodes-langchain.googleGemini - googleGemini
Config choices: Version 1

Block 15 - Sticky Note6

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

Block 16 - Sticky Note7

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

3. Summary Table

Workflow	Process large documents with OCR using SubworkflowAI and Gemini
Complexity	advanced
Nodes	16
Categories	Document Extraction, Multimodal AI
Author	Jimleuk
Published	06 Nov 2025

4. Reproducing the Workflow from Scratch

1. Download the workflow JSON

Use the JSON export at /data/workflows/10566/10566.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 Multimodal AI workflows

Frequently asked questions

What does Process large documents with OCR using SubworkflowAI and Gemini 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, Multimodal AI use case.

Jimleuk

100 workflows

Nodes

n8n-nodes-base.wait n8n-nodes-base.httprequest n8n-nodes-base.manualtrigger n8n-nodes-base.googledrive n8n-nodes-base.splitout n8n-nodes-base.stickynote n8n-nodes-base.if @n8n/n8n-nodes-langchain.googlegemini

Complexity

advanced

Published 06 Nov 2025

Likes 0

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Install path: /data/workflows/10566/10566.json

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Process large documents with OCR using SubworkflowAI and Gemini

Workflow preview

Important notice

1. Workflow Overview

Best for

Tools used

Source and attribution

1.1 Workflow description

Working with Large Documents In Your VLM OCR Workflow

Prequisites

How it Works

How to use

Customising the workflow

Need Help?

1.2 Logical Blocks

2. Block-by-Block Analysis

Block 1 - Wait

Block 2 - Check Job Status

Block 3 - Get Dataset Items

Block 4 - Get Dataset

Block 5 - When clicking ‘Execute workflow’

Block 6 - Download file

Block 7 - Split Out

Block 8 - Sticky Note

Block 9 - Extract API

Block 10 - Sticky Note1

Block 11 - Sticky Note2

Block 12 - Sticky Note4

Block 13 - Job Complete?

Block 14 - Document OCR via VLM

Block 15 - Sticky Note6

Block 16 - Sticky Note7

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