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How to compress a PDF to 100 KB for an upload form
Get a PDF under 100 KB, 200 KB or 1 MB for an application portal: what the tool tries first, why pages sometimes become images, and what to do if it won't fit.
New
Tool
Annotate PDF
Mark up a PDF the way you would on paper. Draw freehand, write notes, point things out with arrows and boxes, and highlight text in yellow, green, pink or blue: the highlighter snaps to the lines of text. Then save it to share.
Drop a PDF here
or
Your files stay on your device. Nothing is uploaded.
How to annotate PDF
- Choose or drop the PDF.
- Pick the pen, text, highlighter, marker, arrow or box and mark up the page. Change colours and sizes as you go.
- Select “Save annotated PDF” and download it.
Private by design
Most online PDF tools upload your document to their servers. This one doesn’t: Annotate PDF runs entirely in your browser, so contracts, forms, IDs and photos never leave your device. It’s free and adds no watermark, and you don’t need an account.
Questions
Can other people see my annotations?
Yes. They're saved into the page, so they appear in every PDF viewer and when printed.
Can annotations be edited later in Acrobat?
They're added to the page content rather than as separate comments, so they look the same everywhere but can't be switched off or edited as comments later.
Does highlighting cover the text?
No. Highlights are blended like real highlighter ink, so the text underneath stays fully readable, on screen and in print.
Can I highlight a scanned PDF?
Scans have no text to snap to, so drag a box with the highlighter or draw with the marker instead. Both work on any page.
Does it work with a stylus?
Yes. The pen and marker follow a stylus, finger or mouse, on tablets as well as computers.
How do I remove a mark?
Before saving, select it and press Delete or use the remove button. After saving, open the original file again, which is never changed.
Are my files uploaded?
No. Every tool runs in your web browser, so your files are read, changed and saved on your own device and never sent to LabAnvil or anyone else. Once the page has loaded, the tools even work offline.
Is it free? Do I need an account?
Free, with no watermark, no daily limit and no account.
Part of PDF Tools
18 free PDF tools that run in your browser: merge, split, compress, convert, edit, sign and fill in PDFs without uploading them anywhere.
A little guidance
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