BASALT · JOURNAL
Free PDF apps and what they trade away
Several capable PDF applications for macOS are free, and it is worth understanding how, because the answer determines whether they suit confidential work.
The usual models
Cloud processing. The application is a front end and the work happens on a server. Free because the operating cost is low per user and the data has value or the model is upsell.
Freemium. Core operations free, the ones professionals need behind a payment.
Data. Usage information, or the documents themselves, contribute to the business.
Genuinely free. Open source projects and command line tools, funded by people who wanted them to exist.
None of these is disreputable. They are different trades, and the one that matters for document work is whether files leave your machine.
The question to ask of any of them
Does this application send my document anywhere?
The answer is often in the privacy policy and always in the behaviour. On macOS you can check the behaviour directly rather than reading the policy:
codesign -d --entitlements :- /Applications/TheApp.appAn application declaring no network entitlement cannot transmit, whatever its policy says. One that declares network access may be entirely benign and you are then relying on the policy.
Evaluating a free tool
Test it on a document you do not mind losing. Check whether processing works offline by turning off wifi. Read what the privacy policy says about uploads and retention. Then decide which documents it is appropriate for, which may be most of them.
Where free stops being enough
The recurring gap is redaction. Covering text is easy and every tool can do it; removing it and proving the removal is harder and few do it. For anything leaving your organisation with material removed, that is the capability that matters, and it is worth testing directly rather than believing a feature list.
Take any tool's redacted output, select the blacked out area, copy, and paste into a plain text editor. Thirty seconds, and it settles the question.
Frequently asked questions
How are free PDF applications funded?
Usually by cloud processing where the work happens on a server, by a freemium model with professional features paid, by data, or by being genuinely free open source. The important question for document work is whether files leave your machine.
How do I tell if a free PDF app uploads my files?
Turn off wifi and see whether processing still works, and on macOS check declared entitlements with codesign -d --entitlements :- against the app. An application with no network entitlement cannot transmit regardless of its policy.
Are free PDF apps safe for confidential documents?
It depends entirely on whether they process locally. Applications that send documents to a server are unsuitable for material under privilege or an NDA, whatever their retention policy says.
What do free PDF tools usually not do well?
Redaction. Drawing a black box is easy and universal; removing content and proving it is gone is harder and rare. Test it by copying the blacked out region of any output and pasting it into a text editor.
Doing it in Basalt
Basalt is a native macOS PDF toolkit: eighteen tools in one window covering merge, split, page organisation, compression, OCR, passwords, Bates numbering, forms, signing, watermarks and comparison. Every file is processed on your Mac, and the engine that opens documents holds no network entitlement at all, which macOS enforces at the code-signature level. Redaction destroys content rather than covering it, and an independent verifier proves the material is gone before a file is written. A one time $29 licence covers up to three Macs, free for the first 24 hours. basaltformac.com, or brew install --cask chipmunk1101/tap/basalt.
Redaction that proves itself
Basalt destroys the content you mark, then re-opens the file it wrote and proves the content is gone before it saves anything. Your documents never leave your Mac.