Highlight important text and sections in your PDF documents. Choose colors, adjust opacity, and download the highlighted PDF. All processing happens in your browser.
or click to browse your files
Mark important text and sections in three simple steps — no software installation or account required.
Drag and drop your PDF file into the upload area, or click "Choose PDF File" to browse your device. The tool accepts any standard PDF document. Once uploaded, every page is rendered so you can navigate to the section you want to highlight.
Choose your preferred highlight color from the palette — yellow, green, blue, pink, orange, or red. Adjust the opacity to control transparency. Then click and drag over the text or sections you want to highlight. Add as many highlights as you need across any page.
Once you are satisfied with your highlights, click the download button to save the edited PDF. All highlights are embedded into the document. Your original file is never modified — a new copy is created with the highlights applied.
The fastest, safest way to highlight PDF documents online — no software needed.
No premium tier, no usage limits, and no hidden fees. Highlight as many PDFs as you need without creating an account or paying a subscription. ConvertKr is free for everyone.
Your files never leave your device. All highlighting happens locally in your browser using JavaScript. There is no server upload, no cloud storage, and no data collection of any kind.
Choose from a full palette of highlight colors including yellow, green, blue, pink, orange, and red. Use different colors to categorize or prioritize different sections of your document for easy visual reference.
Control the transparency of your highlights so underlying text remains perfectly readable. Lower opacity for subtle emphasis or higher opacity for bold, attention-grabbing marks.
Navigate between pages and add highlights to any page in your PDF document. Whether it is a single-page memo or a hundred-page report, every page is accessible for highlighting.
ConvertKr never adds watermarks, logos, or branding to your highlighted PDF. The downloaded file is clean and professional — only your highlights appear on the document.
Everything you need to know about highlighting PDFs with ConvertKr.
ConvertKr provides a wide palette of highlight colors including yellow, green, blue, pink, orange, and red. You can switch between colors at any time and use multiple colors within the same document to organize or categorize content visually.
Yes. The editor supports undo and redo operations, so you can remove a highlight immediately after placing it. You can also select and delete individual highlight annotations before downloading the final PDF.
Absolutely. You can navigate to any page in your PDF and add highlights independently on each page. There is no limit to the number of pages or highlights you can add to a single document.
Yes. When you download the highlighted PDF, the highlights are embedded directly into the document content. They will appear in any PDF viewer, including Adobe Acrobat, Preview, Chrome, and mobile PDF readers.
Yes. The highlights are part of the PDF content, so they will appear when you print the document. The colors are preserved accurately in print, making highlighted PDFs ideal for study notes, review copies, and reference materials.
Yes. ConvertKr's PDF highlight tool is 100% free with no hidden charges, no premium plans, and no signup required. You can highlight unlimited PDF files at no cost.
Yes. The opacity slider lets you control how transparent or opaque each highlight appears. Lower opacity values create subtle, translucent highlights while higher values produce bold, vivid marks. The text underneath always remains readable.
Yes. ConvertKr runs entirely in your web browser, so it works on smartphones and tablets. The interface is responsive and touch-friendly, making it easy to highlight PDFs on iOS and Android devices.
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