Privacy policy

Who this covers

This policy covers the PowerLens website and app (“PowerLens”), including the installable version and the single-file version. It applies to everyone who uses them.

PowerLens is made by BARGE Studios Inc. (“we”, “us”), a company incorporated in Delaware. See bargestudios.com. Questions about this policy can be raised through the project’s issue tracker.

Your documents

When you choose, drop or paste a document, image or recording, it is read by code running in your browser. Comparing, copying changes, reviewing and exporting all happen there too. The contents of your files are not sent to us unless you choose one of the two features that need our server: keeping a comparison there, or transcribing recordings there. Both are described below.

The same is true of the samples: they are downloaded from this site like any other page, then read in your browser.

What we collect

Nothing about you, and nothing of your documents unless you choose a feature that needs our server (below). PowerLens has no sign-up, no analytics, no advertising and no tracking pixels, and it sets no cookies until you use its server (see cookies and storage).

Like any website, the service that hosts PowerLens’s pages may keep standard server logs, such as the IP address that asked for a page, the time and the browser’s user agent, to run and protect its service. Those logs are handled under the hosting provider’s own privacy policy. They never include your documents.

What stays in your browser

So that a reload doesn’t lose your work, PowerLens keeps some things in your browser’s own storage, on your device:

• the current comparison: both documents, the changes you copied and your place in them;
• your notes, highlights, decisions and the name you put on your notes;
• your view settings, theme and words you added to the spelling dictionary;
• the site’s pages and tools, so it works offline once installed.

We can’t see any of it. It stays until you clear it, and a private window forgets it when it closes. The cookies and storage page lists every item and how to clear them.

What our server keeps, if you choose

Two features keep something on PowerLens’s own server. Neither is used unless you choose it:

• Keeping a comparison on the server. When you start or save a comparison, you choose where it is kept. Kept in this browser (the first choice), nothing is sent. Kept on the server without the files, the server keeps its title, the two files’ names, sizes, types and fingerprints (SHA-256, to know the files again when you choose them), and what you did with it: your decisions, notes, highlights and transcripts. Kept with the files, it keeps the two files too. It stays until you delete it from your comparisons.
• Transcribing recordings on the server. PowerLens asks first. Each recording is sent as sound only (16 kHz, one channel), without its name, and deleted as soon as it is transcribed (or after a day, if it couldn’t be). The text is kept for a week, so that a page reloaded meanwhile still gets it, and for as long as a comparison you keep on the server holds it.

The server tells which browser saved what by a random id in a cookie (powerlens_client), set the first time you use one of these features. It isn’t tied to your name, email or anything else about you: there are no accounts. A browser that hasn’t visited for 180 days is forgotten, with everything it kept on the server. Clearing this site’s cookies removes the id, and the server can then no longer tell that what it keeps is yours, so delete what you saved first.

For each browser, the server keeps up to 500 MB of files and transcribes up to three hours of recordings a day. Like the pages, its requests may be logged by the hosting provider (IP address, time, browser), never with the files.

When something leaves your browser

Some features need something from, or send something to, another service. Each happens only when you use that feature:

The PDF libraries from jsDelivr are checked against a known fingerprint (subresource integrity), so a tampered copy is refused.

Files you share

A redline, report or .powerlens review file you download is yours, and it contains whatever you put in it, including your notes and the name on them. Who you send it to is up to you. A .powerlens file can be locked with a password (AES-GCM encryption, with the key derived from your password); we can’t recover a forgotten password.

Children

PowerLens is a general-purpose tool and isn’t aimed at children, and it asks no one who they are.

Your rights

Data protection laws such as the GDPR give you rights over personal data held about you. What PowerLens keeps in your browser is under your control there. What our server keeps for your browser, if you chose a feature that needs it, is tied to a random id rather than to you: you can see it and delete it in your comparisons, and transcripts not kept with a comparison are deleted within a week. For anything else, contact us. For data held by a cloud drive, hosting provider or Claude, contact that service.

Changes to this policy

If this policy changes, the new version will be posted here with a new date at the top. A change that collects more data would be explained on this page before it takes effect.

Contact

Questions about privacy can be raised through the project’s issue tracker. Please don’t include the contents of private documents.