redacting pdf files

How to Redact PDF Files

Redacting text, images, and other data within a PDF file in an automated and efficient manner can be difficult to do at the scale required by large enterprises.

Given the importance of maintaining data privacy and regulations such as the Freedom of Information Act, this can be a real problem for large organizations dealing with a wealth of sensitive data. 

Fortunately, solutions like Toolkit Ultimate by ActivePDF enables users to remove and obscure sensitive data within a PDF file in a programmatic and scalable fashion.

In this article, we’ll provide you with information on why and how to programmatically redact data within a PDF file. 

What is Redaction?

Redaction is the process of removing or obscuring visible text and images from a document. There are many ways in which this is done. However, PDF is the preferred option, especially when dealing with high-volume automated processes.

With software such as Toolkit Ultimate, you can confidently remove and obscure information within PDF files so viewers can’t see or search for sensitive information. Because of this, redaction tools have become a necessity in the legal, healthcare, and government industries.

Not only does redaction remove and obscure text information within PDF files, users can also redact specific words, images, or entire pages, as well as remove and replace the text or images with a custom-filled box.

Redacting sensitive data within a PDF is a security measure, keeping the sensitive data from being shared with the world. Once redacted, data such as names, street addresses, social security numbers, etc., will be obscured within the document.

Why Redact Text?

Organizations that are heavily regulated, such as healthcare, legal, and government are often required to redact data within documents to protect sensitive information. One of the best ways to protect large volumes of data from being leaked to the public is to embed a redaction software tool into your enterprise applications.

Securing digital redaction is imperative to the security of your documents, as well as the confidence it instills in the trust of your clients. This is especially true of data within legal, tax, or medical documents.

In today’s world of digital transformation, having the ability to redact data securely and confidentially is a must-have for industries and individuals seeking to protect their clients. There’s a confidence that comes with solid redaction tools, and the reason why it’s a subject we’re exploring here.


PDF Redaction

Before diving into the process of implementing redaction in a PDF file, let's take a moment to go over why redaction within PDF files is important in the first place. As mentioned above, when correctly applied, sanitizing data with the correct redaction tools will not only protect sensitive data from getting into the wrong hands, it also instills a sense of confidence in your clients.

PDF files have become essential when distributing large volumes of digital documents and the backbone of digital transformation. Because PDF files are made up of searchable text and images, they can be processed in various ways without changing the original formatting or losing fidelity. Additionally, PDF files can be easily shared and electronically signed.

With today’s numerous data privacy and security challenges, it can be hard to find the right partner to redact sensitive PDF information from prying eyes. One option is Toolkit Ultimate by ActivePDF, an award-winning PDF tool is a .NET PDF SDK software solution designed for developers, IT administrators, and leading department heads.

Start your Free Trial of Toolkit Ultimate now:

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Choosing PDF Software to Redact Text

There are a few redaction software tools on the market today. Choosing the one that’s best suited for your company or client will be determined by quality and quantity of digital documents you need to redact.

As noted above, Toolkit Ultimate is a PDF manipulation tool that is built for developers, which runs from your own server or workstation. The award-winning Toolkit Ultimate is an industry-leading option, with simple and transparent pricing that opens up hundreds of methods and properties (including redaction) for .NET PDF developers.

ActivePDF also offers redaction through DocSpace, a low-code option that runs on Windows® PC and individual servers. DocSpace is great for individual users without developer experience.

Learn More About DocSpace

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How to Redact Text with Toolkit Ultimate

Before downloading Toolkit, visit the Toolkit GitHub page for examples. For the specific link to a C# sample that redacts a word within a PDF file, click here.

The below screenshot demonstrates Toolkit C# example and its corresponding output PDF file with the redacted word "Toolkit" obscured with black box within the document. 



Following is the result of the document with the word "Toolkit" obscured with a black box:

Redacted Datasheet


One More Thing...

Be sure to review Toolkit Ultimate's sample code in GitHub for more advanced examples in C# and Visual Basic (e.g. changing color, redact money, redact events , excluding regex, redact by region, and more).

By adding variables to the sample scripts or embedding Toolkit Ultimate as a part of a larger program or workflow, developers can significantly streamline their document redaction processes and ease the cost of complying to the Freedom of Information Act and other related e-Discovery requests.

In Conclusion

There you have a quick recap about redacting text within a PDF file. Now that you know the basics of redaction, there's no reason to not use this accurate and secure feature within your PDF files.

Toolkit Ultimate is an award-winning PDF SDK, the flagship product at ActivePDF, and the most effective way to automate redaction within large volumes of PDF files.

To learn more about Toolkit Ultimate and the many ways it is being used by industries around the world, visit the ActivePDF Solutions homepage.

For the full list of configurable options provided by Toolkit Ultimate and Toolkit, access the Toolkit Product page. 

Do you have more questions about redaction, PDF technology, or digital transformation? Contact the knowledgeable technical advisors at ActivePDF today!Speak with a rep




Confidently remove and obscure information within PDF files so viewers cannot see or search for sensitive information. With Redaction in Toolkit Ultimate, you can redact specific words, text, images, or entire pages, as well as remove and replace the text or images with a custom-filled box of your choice.

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