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100% Free ยท Premium Tool

PDF Underline OnlineNEW

Draw clean text underline styles on matches, keywords, or customized page selections offline.

Drag & drop files to underlineor click to browse from your device

How PDF Underline Works

Easily markup and emphasize key concepts in your PDF documents.

1

Upload PDF

Select and load your PDF file directly into your browser window securely.

2

Apply Underlines

Search for specific words to underline them automatically, or draw custom lines by dragging.

3

Download Markup

Export the newly annotated PDF immediately without formatting loss.

Why choose our markup editor?

Underline text elements in seconds using our intelligent search indexing or freehand vector strokes.

Search & Auto-Underline

Type keywords or phrases to instantly highlight all matches across all pages simultaneously.

Adjustable Styling & Colors

Choose custom line weights, select from a professional palette, or pick any hex color.

Completely Client-Side

Your documents never touch a web server. All parsing, rendering, and rendering tasks run in memory.

Normal Text
Underlined

Frequently Asked Questions

Common queries regarding client-side PDF text markups.

Q.Will this affect the original text layers?

No, the underlying text remains copyable and searchable. The lines are vector objects layered precisely relative to text bounds.

Q.Can I choose different colors for different pages?

Yes, you can customize individual line colors, positions, and thickness properties separately for any selection.

Q.Is my data secure?

100% yes. All operations are run locally within your web browser cache. No PDF content is sent to any server.

Q.Can I remove annotations after drawing them?

Yes, select any underline in the preview pane or the sidebar checklist and click the delete icon to remove it.