# Fill any PDF from JSON data with JustFill and Gemini: n8n workflow

> Started by someone submitting a form. It calls services over plain HTTP rather than through connectors. 20 steps: a working afternoon to understand properly.

Source: https://millionrounds.com/workflow/fill-any-pdf-from-json-data-with-justfill-and-gemini (Millionrounds; every figure on the page links to its filing or article)

[Automation library](https://millionrounds.com/workflows) · [Documents and files](https://millionrounds.com/workflows?category=Documents+and+files#library)

# Fill any PDF from JSON data with JustFill and Gemini

Started by someone submitting a form. It calls services over plain HTTP rather than through connectors. 20 steps: a working afternoon to understand properly.

Medium

[Download free](https://millionrounds.com/login?next=%2Fapp%2Fworkflow%2Ffill-any-pdf-from-json-data-with-justfill-and-gemini)

**20 steps** Medium: a working afternoon

**0** Branches: places the flow splits

**0** Loops or waits

**0** Services by connector: it calls them over plain HTTP

## The flow

Starts it 1 Logic 10 Service 9

The steps in the order they run, from what starts it.

- 1 **On form submission** Form trigger *Starts it*
- 2 **Config** Set *Logic*
- 3 **Mint upload slot** Http Request *Service*
- 4 **Prepare upload** Code *Logic*
- 5 **Upload PDF** Http Request *Service*
- 6 **Open PDF** Http Request *Service*
- 7 **Prepare page previews** Code *Logic*
- 8 **Render preview** Http Request *Service*
- 9 **Attach page preview** Code *Logic*
- 10 **Build mapping request** Code *Logic*
- 11 **Mapping vision model** Http Request *Service*
- 12 **Validate mapping** Code *Logic*
- 13 **Render filled preview** Http Request *Service*
- 14 **Attach filled preview** Code *Logic*
- 15 **Build validation request** Code *Logic*
- 16 **Review vision model** Http Request *Service*
- 17 **Require approval** Code *Logic*
- 18 **Fill PDF** Http Request *Service*
- 19 **Result** Code *Logic*
- 20 **Redirect to filled PDF** Form *Service*

## How it's built

- **Starts on:** Someone submitting a form
- **Steps:** 20
- **Size:** Medium: a working afternoon
- **Connects to:** Nothing by connector; it calls services over plain HTTP
- **Model:** None. This is plumbing, not judgement

## Questions

What does it need to run?

An n8n account. You connect your own accounts after importing it; none are included.

What starts it?

It starts on someone submitting a form.

Does it use AI?

No. Every step is fixed logic or a call to a service, so it does the same thing every time.

How long does it take to set up?

Plan an afternoon. 20 steps is enough that you should read each one before running it.

How do I import it?

Copy the workflow, open a new workflow in n8n and paste. The steps appear on the canvas, ready for your own accounts.

**Before you run it**

Nothing here has been tested by us. It is somebody's working automation, read and described from its own steps. Treat the connections it wants as a list of accounts it will touch, and read the 20 steps before you point it at anything that matters.

## Run it in n8n

- **Create your n8n account** Free to start. n8n is where the workflow runs. [Create an n8n account ↗](https://millionrounds.com/n8n)
- **Download the workflow** Free with a Millionrounds account. [Download free](https://millionrounds.com/login?next=%2Fapp%2Fworkflow%2Ffill-any-pdf-from-json-data-with-justfill-and-gemini)
- **Paste it into n8n** Open a new workflow in n8n and paste. Then connect your own accounts.

Stored with the author's traces removed: canvas notes, instance identifiers, saved credential names and any live document they had left behind.

## Workflows like it

Also documents and files, with the same services where possible, closest in size first.

- [**Automated database backup with Google Sheets and Slack** 20 steps · Google Sheets, Slack](https://millionrounds.com/workflow/automated-database-backup-with-google-sheets-and-slack)
- [**Backup your credentials to GitHub** 20 steps · GitHub](https://millionrounds.com/workflow/backup-your-credentials-to-github)
- [**Extract and triage PDF documents with Claude and Gmail** 20 steps · Airtable, Gmail](https://millionrounds.com/workflow/extract-and-triage-pdf-documents-with-claude-and-gmail)
- [**Parse Google Drive documents to RAG-ready Markdown** 20 steps · Google Drive, Supabase](https://millionrounds.com/workflow/parse-google-drive-documents-to-rag-ready-markdown)
- [**Restore workflows and credentials from remote FTP backup storage** 20 steps · Email, FTP](https://millionrounds.com/workflow/restore-workflows-and-credentials-from-remote-ftp-backup-sto)
- [**Translate PDFs into multiple languages with Google Translate** 20 steps · Gmail, n8n data table](https://millionrounds.com/workflow/translate-pdfs-into-multiple-languages-with-google-translate)