PDF Viewer

Opening a PDF online normally means uploading it, which for a great many documents is the thing you were trying to avoid — a contract under negotiation, a medical letter, a bank statement, an unreleased report. The moment it leaves your machine you are relying on someone else's retention policy.

This viewer renders the document in your own browser. The file is read from your disk, decoded and drawn on your screen by code running in the tab, and no part of it is transmitted. That is also true of the password when you open an encrypted document: it is used locally to decrypt and goes nowhere.

The practical upshot is that it works with no account, no upload wait, and no question about where the document ended up. It also works offline once the page has loaded.

The tools cover the vocabulary of reviewing a document: highlighting a passage, underlining, striking through what should go, drawing freehand around a diagram, dropping a sticky note where a comment belongs, and adding a text box where something needs writing in. The comments panel gathers them so you can see everything you have flagged without scrolling the whole document.

When you save, the markup is flattened into the pages. That is the deliberate choice: annotations stored as separate PDF objects are shown differently by different viewers and are sometimes hidden entirely, so a reviewer's comments can silently vanish on the recipient's screen. Flattened markup is part of the page and displays identically everywhere, including on paper.

The cost is that flattened annotations cannot be individually edited later. Keeping the original alongside the annotated copy is the habit that makes this a non-issue.

Reading a two-hundred-page document is a navigation problem before it is a reading problem. Text search is the fastest route to a specific clause or figure, and it works wherever the document has a text layer — which is every born-digital PDF and no scan until OCR PDF has been over it.

Zoom matters more than people expect for dense material. Fitting the page width usually beats fitting the whole page for anything with body text, since a full page view on a laptop renders 11-point type at a size that is technically visible and genuinely tiring.

Where a document will be consulted repeatedly rather than read once, adding an outline with Edit Bookmarks pays for itself immediately — a navigation panel turns scrolling into jumping, and the bookmarks travel with the file for everyone else who opens it.

This is for reading and marking up. Changing the document itself is a different job: Edit PDF changes the text already on the page, adds form fields and inserts content, which is more than a viewer should attempt.

Page-level work has its own tools too — Organize PDF for reordering and rotating, Delete Pages and Extract Pages for the page list, Merge PDF for combining documents. Doing those in a viewer tends to produce tools that are worse at both jobs.

And if a marked-up document is going onwards, the finishing tools apply as normal: Compress PDF for size, Protect PDF for a password, Sign PDF for a signature on the reviewed copy.