Useful Tools Online

PDF Studio

Add text, annotate, sign, watermark, and organize — processed locally on your device.

Local

Edit and annotate PDFs in your browser

Free, full-featured PDF editor. Add text notes, high-resolution drawings, custom signatures, watermarks, and page numbers with 100% client-side privacy.

Choose or drop PDF to begin

or drag and drop here

PDF only · up to 100 MB per file · processed locally in your browser

Files never leave your device. Processed locally in memory.

Draw & Highlight

Freehand pen drawing with custom stroke width and colors, plus semi-transparent highlighter rectangles for markup.

Sign & Stamp

Draw digital signatures directly on canvas or upload signature stamps. Place, rotate, and scale them on any page.

Text Overlays & Notes

Add crisp vector text boxes with customizable fonts, sizes, colors, and line wraps over existing document layouts.

Watermarks & Numbering

Batch-apply diagonal text watermarks, logo stamps, and sequential header/footer page numbers across all pages.

Multi-Page Organization

Navigate through thumbnails, reorder pages, rotate orientations, and export high-fidelity modified PDFs.

100% Private & Safe

Everything runs in WebAssembly and browser memory. No server uploads, no logins, and zero document telemetry.

How to Edit a PDF Online

  1. 1. Upload DocumentDrag and drop your PDF file or click to select from your device.
  2. 2. Annotate & EditUse the top toolbar to insert text, signatures, highlights, drawings, or watermarks.
  3. 3. Export & DownloadClick Export PDF in the top right to download your finished document instantly.

Frequently Asked Questions

Is PDF Studio completely free?
Yes. PDF Studio is free without accounts, trial periods, or exported watermarks.
Are my confidential PDF documents private?
Yes. PDF Studio executes all PDF parsing and rendering inside your local browser sandbox. No file data is sent to external servers.
Can I edit existing text in the original PDF?
PDFs are fixed-layout vector documents. You can add new text overlays, notes, and redactions over existing elements.