How to Highlight Text In PDF
Highlighting key passages, important figures, and critical clauses in a PDF makes essential information immediately visible when you or others revisit the document. It's the digital equivalent of a highlighter pen—invaluable for studying, legal review, research, and contract analysis. SublimePDF lets you highlight text in multiple colors with options to add notes and export highlighted passages.
Follow the step-by-step instructions below, then use the free tool directly — no registration or download required.
Open Tool →How to Highlight Text In PDF — Step by Step
Upload your PDF
Open the Highlight Text tool and upload the document. The text becomes selectable—move your cursor over the page and you'll see the text selection tool is active.
Select text to highlight
Click and drag across the text you want to highlight. The selection follows the text flow, handling multi-column layouts and wrapped lines correctly. Release the mouse button to apply the highlight.
Choose highlight color
Pick from standard colors: yellow (general emphasis), green (important/agreed), pink (critical/urgent), blue (informational), or orange (action items). Consistent color usage makes review more efficient.
Add notes to highlights
Double-click any highlight to attach a note. This is useful for explaining why a passage is important or flagging a specific question or action item related to that text.
Save or export highlights
Save the highlighted PDF to share with others. Optionally, export a 'Highlights Summary' document that lists all highlighted passages with their colors, page numbers, and attached notes.
Pro Tips
- 💡 Establish a color-coding system before you start: e.g., yellow for key facts, green for supporting evidence, pink for contradictions or concerns, blue for definitions.
- 💡 Use the 'Highlights Summary' export for studying—it extracts all highlighted text into a condensed review document.
- 💡 For long documents, use the keyboard shortcut (H) to toggle the highlight tool on and off without moving to the toolbar each time.
- 💡 If you're reviewing a contract, highlight favorable terms in green and unfavorable terms in red to create a visual map of the agreement's strengths and weaknesses.
Privacy & Security
All processing happens directly in your browser. Your files are never uploaded to any server — they remain on your device throughout the entire process. SublimePDF uses WebAssembly technology for fast, secure, client-side processing.
Works Everywhere
This tool works on any modern browser — Chrome, Firefox, Safari, or Edge — on desktop, tablet, or mobile. No software to install. PDF is an open ISO standard supported by all major platforms.
How to Highlight Text In PDF — FAQ
Can I highlight text in a scanned PDF?
Can I remove or change a highlight after applying it?
Will highlights appear when I print the PDF?
Can I search for text and highlight all matches at once?
Related Guides
How to Convert Scanned PDF to Text
Scanned PDFs are essentially images — you can't select or search the text. OCR (Optical Character Recognition) technology converts these image-based PDFs into searchable, editable text. SublimePDF's OCR tool handles this conversion right in your browser.
How to Edit Text in a PDF
Need to fix a typo, update a date, or add text to a PDF? SublimePDF lets you edit text directly in the PDF without converting to another format first.
How to Add Text To PDF
Sometimes you need to add a note, fill in a missing field, label a diagram, or stamp a status like 'APPROVED' or 'DRAFT' directly onto a PDF without converting it to another format. Adding text directly to a PDF preserves the original layout while layering your additions on top. SublimePDF's text tool gives you full control over font, size, color, and exact placement.