Annotate PDF

Mark up a PDF like you'd mark up a paper page.

Highlight the parts that matter. Strike through the parts that don't. Drop a comment where you need someone to look. Works on any PDF, in your browser, free.

Start here

Upload your file to start

Supported formats: PDF input with annotated PDF output.

PDFSingle file

Upload a PDF to annotate

Drag and drop or click to browse. Pdf Clarity opens the editor in a markup-first review mode.

Drop files anywhere inside this panel.Processed locally — we never keep it.
Processed locallyFiles stay on this deviceNo account wallTrust details

What happens next

Your file opens in the matching tool so you can edit, convert, or export it without uploading it a second time.

  • No signup
  • No watermarks
  • Files deleted after 1 hour

Encrypted upload. Deleted in an hour. Never shared. Never trained on. Ever.

ISO/IEC 27001 (in progress)
GDPR compliant
TLS 1.3
Files deleted after 1 hour
No signup required

How to mark up a PDF, end to end.

Four clicks from a dropzone on this page to an annotated PDF in your Downloads folder. You never leave the tab.

  1. Drop your PDF on this page.

    Drag it from your desktop or click to browse. It uploads encrypted. We can't see it.
  2. Pick a markup tool.

    Highlight, sticky note, strikethrough, underline, shapes, arrows, or the pen — whichever one fits the mark you want to leave.
  3. Mark up the page.

    Drag across the text. Drop the note. Circle the figure. You can stack as many marks as you want on the same page without slowing anything down.
  4. Download. We forget.

    Your annotated PDF lands in Downloads. Our copy is deleted within the hour. Nothing to clean up later.

What you can actually do on this page.

Five honest markup moves you can finish in the browser you're already in. No Adobe, no signup, no half-features held behind a paywall.

  • Highlight in six colors.

    Drag across a passage and it lights up in yellow, green, pink, blue, orange, or purple. The markup stays crisp at every zoom level.

  • Sticky comments for the stuff that needs explaining.

    Drop a note anywhere on the page. The reader clicks it to expand the comment. The page still looks clean until they do.

  • Strikethroughs and underlines for the boring stuff.

    Cross out the sentence that's wrong. Underline the one that isn't. Both survive export and open cleanly in any PDF reader.

  • Arrows and shapes for the "look here" moments.

    Circle the figure. Point an arrow at the one paragraph that matters. Rectangles, ovals, lines, arrows — pick the one that reads loudest.

  • Freehand ink when you need to sketch.

    Grab the pen tool and draw straight on the page. Perfect for circling a problem, scribbling a correction, or signing a quick note.

Why people choose Pdf Clarity

  • Private by default

    Your PDFs are transferred over TLS and deleted within one hour. We don't look at them, and you don't need an account.

  • Fast and free

    Editing, annotating, signing, merging and splitting are free with no signup. Your first upload opens the editor in seconds.

  • Works in any browser

    Open the editor in Chrome, Safari, Firefox or Edge on Mac, Windows, Linux or Chromebook. You never install anything.

More ways to mark up a PDF

Highlight PDF online

Drag across any passage to highlight it in the color you want. Your highlights export clean and stay sharp when the next person opens the PDF.

Add sticky notes to a PDF

Drop a sticky note beside any paragraph to leave a longer comment for your reader. Every note you add collapses into a small marker so the page still looks clean until someone clicks to expand it.

Draw on a PDF

Use the pen tool to circle a figure or sketch a correction directly on the page. Your freehand ink stays smooth and flattens cleanly into the exported PDF.

Add shapes to a PDF

Drop rectangles, arrows, or ovals to call out the area your reader should see first. You can layer as many shapes as you want without slowing the viewer down.

Frequently asked questions

Quick answers to what people ask us most about editing a PDF online for free. Tap any question and the answer expands inline.

Is it really free? What's the catch?
There isn't one. Highlighting, commenting, shapes, ink, sticky notes — all free, for as long as you need it. No signup, no watermark, no trial timer.
Will the finished PDF have a watermark?
Never. Not on free, not on Pro, not ever.
What happens to my file after I'm done?
Deleted within one hour of upload. Encrypted in transit and at rest. Never read by a human, never shared, never used to train anything.
Do I need to sign up, create an account, or enter an email?
No, no, and no. The button says "Drop your PDF here" — that's the whole onboarding.
Can I add sticky notes and shapes?
Yes — sticky notes, rectangles, ovals, lines, arrows, and freehand ink are all free. You can layer them on the same page without limits.
Does it work on an iPad, Chromebook, or phone?
Yes. Any browser — Chrome, Safari, Firefox, Edge. Touch markup works; a stylus or trackpad is smoother for freehand ink.
Can I annotate a scanned PDF?
You can highlight and draw on any page, even a scan. If you need to highlight specific words in a scan, run OCR first (link below) so your text becomes selectable.
Can I save halfway and come back later?
You'd need to re-upload — we delete our copy on purpose. Most people download the in-progress file, keep it locally, and come back for another pass later.
Can I collaborate with someone else on the same annotations?
This page is built for solo markup. If you need real-time collaboration on the same file, Adobe or Dropbox handle that better — we'd rather tell you than pretend.

Related PDF tools

Learn more

Ready to keep reading? You can go deeper on common tasks in the help center articles below.

You can also browse all PDF tools from the tools hub.