PDF Form Filling Guide
This guide covers how to fill PDF forms programmatically.
Prerequisites
Install required packages:
pip install pypdf pdfrwBasic Form Filling
from pypdf import PdfReader, PdfWriter
def fill_form(input_path, output_path, field_data):
reader = PdfReader(input_path)
writer = PdfWriter()
# Clone the original PDF
writer.clone_document_from_reader(reader)
# Fill form fields
for page in writer.pages:
writer.update_page_form_field_values(page, field_data)
# Save the filled PDF
with open(output_path, "wb") as f:
writer.write(f)Supported Field Types
- Text fields
- Checkboxes
- Radio buttons
- Dropdown lists
Tips
- Use
scripts/analyze_form.pyto discover available fields - Field names are case-sensitive
- Always verify output after filling