Extract form data from PDF: web app, CLI, MCP and C# (FOSS)

What it does

Extracts the values of interactive form fields (text boxes, checkboxes, radio buttons, dropdowns, etc.) from a fillable PDF form and outputs them as CSV files.

Inputs and limits

• Input: a PDF file that contains AcroForm or XFA form fields.
• The tool works with fillable PDFs; scanned or non‑interactive PDFs need OCR first and may not produce results.
• No explicit size limit is documented; the CLI and libraries process files that fit into available memory.

Web app

Upload a PDF form on the page Extract Form Data from PDF. The service extracts the field values and returns CSV files with the form data.

Command line (CLI)

Run the Documentize.ExtractFormData plugin, placing the PDF in the task’s input folder and specifying a task ID. The plugin writes CSV files with the extracted fields to the output folder.

# Linux / macOS (needs the .NET 10 runtime and documentize.lic next to the DLL)
export PLUGIN_INPUT_DIR=./work/input
export PLUGIN_OUTPUT_DIR=./work/output
mkdir -p "$PLUGIN_INPUT_DIR/job1"
cp form.pdf "$PLUGIN_INPUT_DIR/job1/"
dotnet Documentize.ExtractFormData.dll --task-id job1
ls "$PLUGIN_OUTPUT_DIR/job1"

# Windows PowerShell
$env:PLUGIN_INPUT_DIR  = "$PWD\work\input"
$env:PLUGIN_OUTPUT_DIR = "$PWD\work\output"
New-Item -ItemType Directory -Force "$env:PLUGIN_INPUT_DIR\job1" | Out-Null
Copy-Item form.pdf "$env:PLUGIN_INPUT_DIR\job1\"
dotnet Documentize.ExtractFormData.dll --task-id job1
Get-ChildItem "$env:PLUGIN_OUTPUT_DIR\job1"

MCP

Call the hosted MCP tool ExtractFormData with a public URL of the PDF form. The service returns a task ID and, upon completion, provides CSV files containing the form data.
Client configuration (the key comes from your Documentize account):

{
  "mcpServers": {
    "documentize": {
      "url": "https://api.documentize.app/mcp",
      "headers": {
        "Authorization": "Bearer dmk_YOUR_KEY_HERE"
      }
    }
  }
}

Tool call (tools/call). The tool returns a task id; poll get_task_status until it reports 200, then download the file from uploadFileName:

{
  "name": "extract_form_data",
  "arguments": {
    "fileUrl": "https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf"
  }
}

Aspose.PDF.FOSS (C#)

A C# program using the Aspose.PDF.FOSS library loads the PDF, iterates over its form fields, and writes a CSV file with field names and values.

#:package Aspose.PDF.FOSS@26.11.0

using Aspose.Pdf;
using System.IO;

var inputDir = args[0];
var outputDir = args[1];
var inputFile = Path.Combine(inputDir, "form.pdf");
var doc = new Document(inputFile);
using var writer = new StreamWriter(Path.Combine(outputDir, "form_fields.csv"));
writer.WriteLine("FieldName,Value");
foreach (var field in doc.Form.Fields)
{
    writer.WriteLine($"{field.PartialName},{field.Value}");
}
Console.WriteLine("form_fields.csv written");

Save it as app.cs and run dotnet run app.cs -- ./in ./out (.NET 10 SDK).

Verified

Every code sample on this page was run on 2026-11-03 and its result was checked:

• Extract form data via CLI with content check (CLI plugin): passed in 1 s
• Extract form data via MCP with content check (hosted MCP server): passed in 6 s
• Extract form data via Aspose.PDF.FOSS with content check (Aspose.PDF.FOSS): passed in 10 s