When working with PDF files, you may encounter documents that are password protected. This means that you cannot view or edit the content without entering the correct password. Understanding how to check if a PDF is password protected and determining the correct password is essential for accessing important information. In this guide, we will introduce how to check if a PDF is password protected and determine the correct password using Python and the Spire.PDF for Python library.
Install Spire.PDF for Python
This scenario requires Spire.PDF for Python and plum-dispatch v1.7.4. They can be easily installed in your Windows through the following pip command.
pip install Spire.PDF
If you are unsure how to install, please refer to this tutorial: How to Install Spire.PDF for Python on Windows
Check if a PDF is Password Protected
Spire.PDF for Python offers the PdfDocument.IsPasswordProtected(fileName: str) method to check if a PDF file is password protected. The detailed steps are as follows.
- Specify the input and output file paths.
- Check if the PDF file is password protected or not using the PdfDocument.IsPasswordProtected() method.
- Save the result to a text file.
- Python
from spire.pdf import *
# Specify the input and output file paths
inputFile = "Secured.pdf"
outputFile = "CheckPasswordProtection.txt"
# Check if the input PDF file is password protected
isProtected = PdfDocument.IsPasswordProtected(inputFile)
# Write the result into a text file
with open(outputFile, "w") as fp:
fp.write("The PDF is " + ("password protected!" if isProtected else "not password protected!"))
Determine the Correct Password for a PDF
While Spire.PDF for Python does not provide a direct method to check if a password is correct, you can achieve this by attempting to load the PDF with the password and catching exceptions. If the password is incorrect, an exception will be thrown. The detailed steps are as follows.
- Specify the input and output file paths.
- Create a list of potential passwords to test.
- Iterate through the list and load the PDF with each password using the PdfDocument.LoadFromFile(filename: str, password: str) method.
- If no exception is thrown, the password is correct. Otherwise, the password is incorrect.
- Save the results to a text file.
- Python
from spire.pdf import *
# Specify the input and output file paths
inputFile = "Secured.pdf"
outputFile = "DetermineCorrectPassword.txt"
# Create a list of potential passwords to test
passwords = ["password1", "password2", "password3", "test", "sample"]
# Create a text file to store the results
with open(outputFile, "w") as fp:
for value in passwords:
try:
# Load the PDF with the current password
doc = PdfDocument()
doc.LoadFromFile(inputFile, value)
# If successful, write that the password is correct
fp.write(f'Password "{value}" is correct\n')
except SpireException:
# If an exception occurs, write that the password is not correct
fp.write(f'Password "{value}" is not correct\n')
Apply for a Temporary License
If you'd like to remove the evaluation message from the generated documents, or to get rid of the function limitations, please request a 30-day trial license for yourself.
