I Built a Free PDF Annotator (Because Adobe Charges $240/Year for That)

I needed to highlight and annotate a legal document for work. You know the drill — open Adobe Acrobat Pro, click highlight, select text, done.

Except I don't have Adobe Acrobat Pro. It's $240 a year. And every time I've tried the free trial, it asks me to create an account, enter payment info, and upload my documents to their cloud.

My documents are confidential. I shouldn't have to upload them just to highlight a paragraph.

So I built something better.

PDF Annotator & Highlighter is a free, client-side tool that runs entirely in your browser. No uploads. No accounts. No subscriptions. No $240/year.

What it does:

• Upload any PDF (drag & drop or click to browse)
• Highlight text with color — yellow, green, blue, or red
• Underline passages
• Add text notes anywhere on the page
• Freehand draw with a pen tool (adjustable width)
• Eraser to remove annotations
• Download the annotated PDF instantly

Everything happens locally using pdf-lib and pdf.js. Your files never leave your device.

Why this matters

Most PDF annotation tools follow the same playbook: free for one or two tasks, then pay up. Adobe Acrobat Pro is the gold standard — but it costs $240/year, requires a subscription, and pushes your documents into the cloud for "advanced" features.

For legal professionals, students, and freelancers who annotate documents daily, that's a privacy problem and a wallet problem.

This tool solves both: it's free, private, and works offline after the first load.

The tech

The whole app is a single HTML file. It uses:

• pdf.js (Mozilla) to render PDF pages to canvas
• pdf-lib to read, annotate, and export PDFs
• Pure Canvas API for the annotation overlay
• Zero server-side processing

No Node.js backend. No database. No tracking. Just a browser tool that does one thing well.

Open and use it

No signup, no install, no tricks. Just open the tool, upload your PDF, and go.

Try the free PDF Annotator & Highlighter

Built because annotating a PDF shouldn't cost $240/year or your privacy.