Software Alternatives, Accelerators & Startups

uMatrix VS KeptPDF

Compare uMatrix VS KeptPDF and see what are their differences

uMatrix logo uMatrix

uMatrix: A point-and-click matrix-based firewall, with many privacy-enhancing tools.

KeptPDF logo KeptPDF

Redact, edit, OCR, and sign PDFs entirely in your browser. The file never leaves your device. Free, no account needed.
Visit Website
  • uMatrix Landing page
    Landing page //
    2023-09-26
  • KeptPDF Landing page
    Landing page //
    2026-08-22

KeptPDF is a PDF toolkit that runs entirely in your browser. Nothing uploads: every tool runs on your own device, so the document never touches a server.

What it does:

  • Redaction that auto-detects names, SSNs, phone numbers, addresses, and dates, then removes the underlying text instead of drawing a box over it. Every redacted file gets an audit certificate that anyone can verify.
  • OCR that makes scanned PDFs searchable, with on-device processing.
  • Sign, annotate, compare, organize, split, merge, compress, convert, watermark, Bates numbering, exhibit stamps, and more. About 25 tools in total.
  • A command line version runs the same redaction engine on your own servers for bulk work: scanning bureaus, litigation support teams, and records departments process thousands of PDFs in one pass.

Who it is for: law firms, accounting practices, clinics, and anyone who shares documents they cannot afford to leak.

The core tools are free with no sign-up. Works offline as an installable app.

KeptPDF

$ Details
freemium $29 / Monthly (Pro, 1 user)
Release Date
2026 May
Startup details
Country
United States
State
Tennessee
Founder(s)
John Whitworth

uMatrix features and specs

  • Advanced Privacy Control
    uMatrix gives users detailed control over what kind of requests (scripts, iframes, XHR, etc.) are allowed to load on every website they visit, enhancing privacy.
  • Customizability
    Users can create highly specific rules for different sites and types of content, allowing for a tailored browsing experience.
  • Enhanced Security
    By blocking unwanted scripts and other potential attack vectors, uMatrix helps to protect users from malicious content and exploits.
  • Open Source
    As an open-source project hosted on GitHub, uMatrix allows for community review, transparency, and contributions to its codebase.

Possible disadvantages of uMatrix

  • Complexity
    The level of granularity and control that uMatrix offers can be overwhelming for non-technical users, making it less accessible to the average user.
  • Configuration Time
    Setting up uMatrix to work optimally for the user's specific needs can be time-consuming, particularly for those who frequent many different websites.
  • Learning Curve
    Understanding how to effectively use all of the features and settings in uMatrix requires a significant investment of time and effort, which might deter some users.
  • Potential Website Breakage
    Due to its aggressive blocking policies, uMatrix can sometimes break website functionality until the user whitelists or configures specific site settings.

KeptPDF features and specs

  • Simple PDF Editing
    KeptPDF offers straightforward tools for editing, merging, splitting, and converting PDF files, making it accessible for users who need quick document management without a steep learning curve.
  • Web-Based Accessibility
    Being a web-based tool, KeptPDF can be accessed from any device with an internet connection, eliminating the need for software installation and allowing use across different operating systems.
  • Multiple File Format Support
    The platform supports conversion between PDF and various other file formats, offering flexibility for users who work with documents in different formats.
  • No Installation Required
    Since it operates in a browser, users can save storage space on their devices and avoid compatibility issues that sometimes arise with desktop software installations.
  • Quick Processing
    KeptPDF is designed to process PDF tasks efficiently, allowing users to complete common document tasks like compression or conversion in a relatively short amount of time.

Analysis of uMatrix

Overall verdict

  • Yes, uMatrix is a good tool if you prioritize privacy and want granular control over what web content can be loaded. However, it may come with a learning curve and is not actively maintained as of its last updates, which could be a drawback for some users.

Why this product is good

  • uMatrix is regarded as a good tool for privacy-conscious users because it allows detailed control over the requests that websites can make within your browser. It offers features such as blocking scripts, iframes, cookies, and other elements, providing users with enhanced security and improved loading times for websites.

Recommended for

  • Users who want to increase their online privacy and security.
  • Tech-savvy individuals who are comfortable configuring detailed settings.
  • Those who wish to reduce the amount of unwanted content and tracking on websites.

uMatrix videos

How to use uMatrix to protect your online privacy & improve security | uMatrix tutorial

More videos:

  • Review - der.hans: uMatrix for Web Browser Protection
  • Tutorial - How to use uMatrix for Online Privacy

KeptPDF videos

No KeptPDF videos yet. You could help us improve this page by suggesting one.

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Category Popularity

0-100% (relative to uMatrix and KeptPDF)
Security & Privacy
92 92%
8% 8
PDF
0 0%
100% 100
Ad Blockers
100 100%
0% 0
PDF Readers And Editors
0 0%
100% 100

Questions & Answers

As answered by people managing uMatrix and KeptPDF.

What makes your product unique?

KeptPDF's answer:

KeptPDF runs entirely in your browser. Your file, and the text inside it, never leaves your device. Not to an AI, not even to us. You can open your browser's network tab and watch: the document bytes never go out.

Most online PDF tools upload your file to a server first, and some "AI redaction" services quietly send your document text to a third-party model. That is the exact risk people are trying to avoid when they redact something.

KeptPDF also does true redaction. The text is removed from the file, not covered with a black box you can copy out later. Every redaction produces a verification certificate you can share with the file.

Why should a person choose your product over its competitors?

KeptPDF's answer:

Three reasons.

Privacy you can verify, not just a promise. Processing happens locally in the browser, so there is no upload step to trust. We do send anonymous usage counts for quota, and we say so plainly, but never your document.

Real redaction with proof. Removed text is permanently gone, and you get a certificate showing the file was checked for leftover extractable text. Automated detection cannot catch everything, so a final human review is still your job, and the tool says that too.

It works on a phone. Most PDF suites assume a desktop. KeptPDF was built and used on a phone first, so redacting a document while you are standing in a hallway actually works.

How would you describe the primary audience of your product?

KeptPDF's answer:

Anyone who has to hand a document to someone else and needs the sensitive parts gone first.

In practice that is solo attorneys and small law firms, accountants and tax preparers, healthcare and records staff handling requests, HR teams, and individuals dealing with their own medical, legal, or financial paperwork.

The common thread is not an industry. It is a person who cannot upload a confidential file to a random website, and who does not have an enterprise IT budget to solve it.

What's the story behind your product?

KeptPDF's answer:

A family member got seriously ill. We spent most days at the hospital, and straight answers were hard to come by, so we leaned on AI tools to make sense of the records, notes, and lab results.

But you cannot paste a medical record into an AI chat. You have to strip the names, the ID numbers, the diagnoses first. And almost every tool we found either wanted to upload the whole file to a server, or "auto-redacted" by sending the document text to an online AI. That was the exact thing we were trying to avoid.

Most of this was happening on a phone, at a bedside. So I built the tool I needed: redaction that runs on the device, works on mobile, and never sends the file anywhere. That turned into KeptPDF, which is now a full PDF suite with over 20 tools, all local-first.

Which are the primary technologies used for building your product?

KeptPDF's answer:

The app is plain JavaScript with no front-end framework, which keeps it fast and keeps the code auditable.

PDF work happens in the browser using pdf.js for rendering and pdf-lib for writing. Text recognition uses Tesseract running as WebAssembly. Password and encryption handling uses a WebAssembly build of qpdf. It is a Progressive Web App, so it installs and works offline.

The thin server side is Node on Vercel, with Postgres for accounts, Stripe for billing, and Resend for email. None of those ever see a document.

Who are some of the biggest customers of your product?

KeptPDF's answer:

KeptPDF is early and independent, and we do not publish customer names. The product is privacy-first by design: we never see your documents, and we do not track who our users are or what they work on. Publishing a client list would sit badly next to that.

The user base today is mostly solo attorneys, small firms, accountants, and individuals handling their own records.

User comments

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Reviews

These are some of the external sources and on-site user reviews we've used to compare uMatrix and KeptPDF

uMatrix Reviews

22 NextDNS Alternatives
uMatrix is a matrix-based point-and-click firewall with plenty of exciting and secure privacy-enhancing tools. Users can point and click to allow as well as forbid any class of requests made by the browser that you have for exploring the internet. Surf the internet while getting rid of blocking scripts, annoying ads, unhealthy iframes, annoying Facebook sponsors, and other...

KeptPDF Reviews

We have no reviews of KeptPDF yet.
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Social recommendations and mentions

Based on our record, uMatrix seems to be more popular. It has been mentiond 5 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

uMatrix mentions (5)

KeptPDF mentions (0)

We have not tracked any mentions of KeptPDF yet. Tracking of KeptPDF recommendations started around Aug 2026.

What are some alternatives?

When comparing uMatrix and KeptPDF, you can also consider the following products

uBlock Origin - Popular and efficient blocker for Chromium, Chrome, Edge, Firefox, Opera, Safari, Thunderbird.

Smallpdf - PDF document management and conversion suite

Adblock Plus - AdBlock Plus is a browser extension for Firefox, Chrome, Opera, and several other popular browsers that prevents intrusive ads like pop-ups and malicious code from appearing on websites you visit.

iLovePDF - Premium online PDF tool set

AdGuard - Surf the Web Ad-Free and Safely. Shield up!

Sejda - Split, merge and other powerful PDF tools.