How to Highlight Text in PDF: Complete Guide

Q: How do I change the highlight color in a PDF?

To change highlight color, the steps depend on your tool: Our online tool: Before highlighting, select a different color from the toolbar (yellow, green, pink, blue, etc.). Highlights applied after that will use the new color. Adobe Acrobat Reader: Right‑click on an existing highlight, choose Properties , then pick a new color from the palette. Click OK. The highlight color changes immediately. Adobe Acrobat Pro: Select the highlight, then use the Color Palette in the top toolbar to change color. You can also set a default color for new highlights. PDF‑XChange Editor: Right‑click the highlight > Properties > Appearance > Fill Color. Choose a new color. Preview (Mac): Click the small arrow next to the highlight button in the markup toolbar and select a different color before highlighting. To change an existing highlight, you must remove it and re‑highlight with the new color. Microsoft Edge: Select a different highlighter color from the toolbar before highlighting existing text cannot be recolored; you need to delete and re‑highlight. Using different colors helps organize feedback (e.g., yellow for general, red for errors, green for approval).

Q: How do I remove or delete highlights from a PDF?

To delete highlights from a PDF: Adobe Acrobat Reader (free) or Pro: Right‑click on the highlighted text and select Delete . To remove all highlights at once, open the Comments panel (right sidebar), click the options menu, and choose Delete All Comments (this removes all annotations, not just highlights). PDF‑XChange Editor: Right‑click the highlight > Delete. Or open the Comments panel, select the highlights you want to remove, and press Delete. Our online tool: Upload the PDF, click on the highlight you want to remove, then click the trash icon (Delete). Download the cleaned PDF. Preview (Mac): Control‑click (or right‑click) the highlighted text and choose Remove Highlight . Microsoft Edge: Right‑click the highlighted area and select Delete . Note: If the PDF has been flattened (printed to a new PDF), highlights become permanent and cannot be removed. Always keep an unflattened copy if you may need to edit highlights later.

Highlighting text in a PDF is one of the most effective ways to emphasize key information, mark important passages, or flag content for later review. Whether you are a student studying for exams, a professional reviewing a contract, or a researcher annotating a paper, knowing how to highlight in PDFs is essential. This guide covers every method to highlight text in PDFs: using online tools (fastest, no installation), Adobe Acrobat Pro & Reader (industry standard), free desktop software (PDF‑XChange Editor), and built‑in viewers (Preview on Mac, Microsoft Edge). You will learn how to change highlight colors, remove highlights, search for highlighted text, and even collaborate with others using highlights. By the end, you will be able to highlight any PDF efficiently, on any device.

Why Highlight Text in a PDF?

Study & revision: Mark key definitions, formulas, or important paragraphs for quick reference.
Document review: Flag sections that need attention, revisions, or approval.
Research & data extraction: Highlight quotes, statistics, or findings to easily extract later.
Collaboration: Use different colors to indicate different types of feedback (e.g., yellow = suggestion, green = approved, pink = error).
Speed reading: Draw attention to main ideas without re‑reading entire pages.

Markup Type	Description	Typical Use	Supported By
Highlight	Colored background overlay over selected text.	Emphasizing text, marking errors, flagging for review.	All tools
Underline	Line drawn beneath text.	Suggested additions, important points.	Acrobat, PDF‑XChange, online tools
Strikethrough	Line drawn through text.	Suggested deletions, outdated content.	Acrobat, PDF‑XChange, online tools
Squiggly underline	Wavy line under text.	Spelling/grammar suggestions, questions.	Acrobat Pro, PDF‑XChange

Method 1: Highlight Text Online (Fastest, No Installation)

Online PDF highlighters are perfect for quick tasks on non‑sensitive files. Do not upload confidential documents.

Using Our Edit PDF Online Tool:

Go to Edit PDF Online.
Upload your PDF.
Click the Highlight button in the toolbar (marker icon).
Select the color you want (yellow, green, pink, blue, etc.).
Drag your cursor over the text you wish to highlight. The text will immediately show the background color.
To highlight multiple sections, continue selecting text. To change color, pick a different color from the toolbar.
Click Download to save the highlighted PDF. Your file is processed in your browser and never uploaded to our servers.

Alternative Free Online Highlighting Tools:

Sejda Highlight PDF: 50 MB limit, 200 pages, 3 tasks/hour. Supports multiple colors, underline, strikethrough.
SmallPDF Highlight PDF: Free tier with daily limits, basic yellow highlight only.
PDFescape (online): 10 MB, 100 pages – supports highlight, underline, strikethrough.
Xodo (online version): Free, no registration, full highlight colors and smooth selection.

Privacy tip: Never upload sensitive or confidential PDFs to any online tool. Use offline software for private documents.

Method 2: Highlight Text Using Adobe Acrobat (Reader & Pro)

Adobe Acrobat Reader is free and offers robust highlighting. Acrobat Pro adds advanced features like highlight summarization and color management.

Adobe Acrobat Reader (Free – Windows, Mac, Mobile):

Open the PDF in Adobe Acrobat Reader.
Select the Highlight tool from the top toolbar (or right‑click on selected text > Highlight).
To highlight: Drag your cursor over the text. The default color is yellow.
To change highlight color: Right‑click on the highlighted text, choose Properties, then select a new color (green, red, blue, etc.).
To delete a highlight: Right‑click the highlighted text and select Delete.
Save the PDF (File > Save).

Adobe Acrobat Pro ($15/month – Advanced Features):

Open the PDF in Adobe Acrobat Pro.
Click Comment in the right panel, then select the Highlight tool.
Use the Highlight Color Palette to set custom RGB colors.
To search for all highlights: Open the Comments panel, then click the filter icon and select “Highlight”.
Export highlights: File > Export > Word / Excel – highlights can be extracted as comments.
For collaborative review, highlights are visible to all users when using “Share for Review”.

Method 3: Highlight Text Using Free Desktop Software (Offline, Private)

These tools work offline and keep your files completely private. Some free versions add watermarks but highlighting remains unaffected.

PDF‑XChange Editor (Free version, Windows):

Open the PDF in PDF‑XChange Editor.
Select the Highlight tool from the Comment & Markup toolbar (marker icon).
Choose a color from the dropdown (yellow, green, cyan, magenta, etc.).
Drag over text to highlight.
To change highlight opacity or style, right‑click the highlight > Properties.
All highlights appear in the Comments panel (left sidebar). You can search, filter, or delete them in bulk.
Save the PDF. The free version adds a small watermark but highlighting remains fully functional.

Preview (Built‑in on Mac, Free):

Open the PDF in Preview.
Click the Markup toolbar button (pencil tip inside a circle).
Click the Highlight button (marker icon).
Select the text you want to highlight. Default color is yellow.
To change highlight color: Click the small arrow next to the highlight button and choose from yellow, green, blue, pink, or red.
To remove highlight: Control‑click (or right‑click) the highlighted text and select Remove Highlight.
Save the PDF (File > Save).

Microsoft Edge (Built‑in on Windows, Free):

Open the PDF in Microsoft Edge browser.
Click the Add notes button (pen icon) in the top toolbar.
Select the Highlighter tool. Choose color (yellow, green, blue, pink, red).
Drag over text to highlight. Edge supports both text selection highlight and freehand highlighter (for images or scanned PDFs).
Click Save (disk icon) to store highlights.

Comparison Table: PDF Highlighting Methods

Method	Price	Multiple Colors	Underline / Strike	Search Highlights	Export Highlights	Privacy
Online Editor (DonePDF)	Free	✅ Yes	✅ Yes (underline)	❌ No	❌ No	Files uploaded
Adobe Acrobat Reader	Free	✅ Yes (via Properties)	❌ No (Reader only highlight)	✅ Yes (Comments panel)	❌ No	Local
Adobe Acrobat Pro	~$15/month	✅ Yes (full palette)	✅ Yes	✅ Yes	✅ Yes (Word/Excel)	Local or cloud
PDF‑XChange Editor (free)	Free (watermark)	✅ Yes	✅ Yes	✅ Yes (Comments panel)	✅ Yes (export to Word)	Local
Preview (Mac)	Free	✅ Yes (5 colors)	❌ No	❌ No	❌ No	Local
Microsoft Edge	Free	✅ Yes (5 colors)	❌ No	❌ No	❌ No	Local

Step‑by‑Step Workflow: Collaborative Highlighting for Team Review

Share the PDF with team members (via email, cloud drive, or shared network).
Each reviewer opens the PDF using their preferred tool (Adobe Reader, PDF‑XChange, or a consistent platform).
Agree on a color code:
- 🟡 Yellow – General important point / needs discussion.
- 🟢 Green – Approved / correct.
- 🔴 Red – Error / needs correction.
- 🔵 Blue – Suggestion / alternative wording.
- 🟣 Pink – Question / clarification needed.
Reviewers highlight text accordingly, optionally adding sticky notes for longer explanations.
If using Adobe Acrobat Pro with “Share for Review”, highlights sync in real‑time.
The lead reviewer compiles all highlights. In Acrobat Pro, export highlights to a Word document for a summary report.
After changes are made, the original author can remove or resolve highlights.

Best Practices for Highlighting PDF Text

Use color codes consistently: Assign meaning to each color before team collaboration.
Don’t over‑highlight: Too many highlights defeat the purpose. Aim for less than 10% of total text.
Combine with notes: Use sticky notes or text boxes to explain why a passage is highlighted.
Highlight only selectable text: Scanned PDFs (image‑based) may not support text highlighting unless OCR is applied first. Use our OCR PDF tool to make scanned text selectable.
Keep a clean copy: Save an unhighlighted version of the PDF as a backup.
Flatten highlights for final distribution: If you want highlights to be permanent and non‑removable, print the PDF to a new PDF (this “flattens” annotations).

Common Mistakes When Highlighting PDFs

Using a browser’s built‑in viewer that doesn’t save highlights: Chrome’s default PDF viewer does not save any annotations. Always use Edge (which saves) or a dedicated tool.
Forgetting to save after highlighting: Online tools require clicking “Download”. Desktop software requires File > Save (Ctrl+S).
Highlighting scanned documents without OCR: You cannot highlight text in a pure image PDF. Run OCR first to make text selectable.
Sharing the wrong version: Make sure you share the highlighted PDF, not the original.
Using too many colors without a legend: Other readers won’t understand your color coding unless you provide a key.

Tools for PDF Management – DonePDF Utilities

Edit PDF Online – Highlight, add sticky notes, text boxes, shapes
OCR PDF – Make scanned PDFs selectable so you can highlight text
Compress PDF – Reduce file size after adding many highlights (compression preserves annotations)
Protect PDF – Prevent others from editing or removing your highlights
Merge PDF – Combine multiple highlighted PDFs from different reviewers

Introduction & Basics

Editing & Annotation

Page Management

Security & Signatures

Use Cases

Conclusion – Master PDF Highlighting in 2026

Highlighting text in PDFs is a fundamental skill for students, professionals, and anyone who works with digital documents. For quick, non‑sensitive PDFs, our free Edit PDF Online tool provides an effortless way to highlight in multiple colors and download the result. For offline privacy and advanced features like searching or exporting highlights, use Adobe Acrobat Reader (free) or PDF‑XChange Editor. Built‑in viewers like Preview (Mac) and Edge (Windows) are great for occasional highlights without installing anything. Remember to use color coding consistently, avoid over‑highlighting, and always save your work. With this guide, you can now highlight any PDF efficiently and collaborate effectively with your team.

Frequently Asked Questions

How can I highlight text in a PDF for free?

You can highlight text in a PDF for free using these methods:

Online (fastest): Use our Edit PDF Online tool. Upload, select the highlighter, choose a color, drag over text, and download. No registration required.
Offline (Windows): Adobe Acrobat Reader (free) – open PDF, select the Highlight tool from the toolbar, drag over text.
Offline (Mac): Preview (built‑in) – open PDF, click Markup toolbar, select the highlighter, drag over text.
Offline (Windows Edge): Microsoft Edge browser – open PDF, click "Add notes", choose the highlighter, drag over text, save.
Offline (Linux / cross‑platform): PDF‑XChange Editor (free version) or Okular (free, Linux/Windows).

For sensitive documents, always use offline tools. For quick, non‑confidential files, online highlighting is fastest.

How do I change the highlight color in a PDF?

To change highlight color, the steps depend on your tool:

Our online tool: Before highlighting, select a different color from the toolbar (yellow, green, pink, blue, etc.). Highlights applied after that will use the new color.
Adobe Acrobat Reader: Right‑click on an existing highlight, choose Properties, then pick a new color from the palette. Click OK. The highlight color changes immediately.
Adobe Acrobat Pro: Select the highlight, then use the Color Palette in the top toolbar to change color. You can also set a default color for new highlights.
PDF‑XChange Editor: Right‑click the highlight > Properties > Appearance > Fill Color. Choose a new color.
Preview (Mac): Click the small arrow next to the highlight button in the markup toolbar and select a different color before highlighting. To change an existing highlight, you must remove it and re‑highlight with the new color.
Microsoft Edge: Select a different highlighter color from the toolbar before highlighting existing text cannot be recolored; you need to delete and re‑highlight.

Using different colors helps organize feedback (e.g., yellow for general, red for errors, green for approval).

How do I remove or delete highlights from a PDF?

To delete highlights from a PDF:

Adobe Acrobat Reader (free) or Pro: Right‑click on the highlighted text and select Delete. To remove all highlights at once, open the Comments panel (right sidebar), click the options menu, and choose Delete All Comments (this removes all annotations, not just highlights).
PDF‑XChange Editor: Right‑click the highlight > Delete. Or open the Comments panel, select the highlights you want to remove, and press Delete.
Our online tool: Upload the PDF, click on the highlight you want to remove, then click the trash icon (Delete). Download the cleaned PDF.
Preview (Mac): Control‑click (or right‑click) the highlighted text and choose Remove Highlight.
Microsoft Edge: Right‑click the highlighted area and select Delete.

Note: If the PDF has been flattened (printed to a new PDF), highlights become permanent and cannot be removed. Always keep an unflattened copy if you may need to edit highlights later.

Why can’t I highlight text in my PDF?

There are several common reasons why you cannot highlight text in a PDF:

Scanned PDF (image‑only): If the PDF is created from scanned pages, the “text” is actually an image. You cannot highlight images as text. Solution: Use an OCR (Optical Character Recognition) tool like our OCR PDF to make text selectable, then highlight.
The PDF has editing restrictions: Some PDFs are password‑protected and disallow commenting or highlighting. Solution: You need the password to remove restrictions, or use a tool that ignores restrictions (not always legal).
Using a browser that doesn’t support saving highlights: Chrome’s built‑in PDF viewer does not allow saving highlights. Use Microsoft Edge, download the PDF and open in Acrobat Reader, or use our online tool.
Corrupted PDF: A damaged PDF might not allow text selection. Try opening it in a different tool or repair it.
Non‑standard fonts or encoding: Rarely, a PDF may use fonts that prevent text selection. Try converting to another PDF using a print‑to‑PDF method.

Most often, the issue is a scanned PDF. Run OCR first, then highlight.

Can I highlight a scanned PDF (image PDF)?

You cannot directly highlight text in a scanned PDF because the page is an image, not selectable text. However, you can use OCR (Optical Character Recognition) to convert the scanned image into selectable text. After OCR, the PDF will contain a hidden text layer that you can highlight normally.

How to highlight a scanned PDF:

Use an OCR tool: DonePDF OCR (free, online) or Adobe Acrobat Pro (built‑in OCR).
Upload the scanned PDF and run OCR. The tool will create a new PDF with selectable text.
Download the OCR‑processed PDF.
Open the new PDF in any highlighter (our online tool, Acrobat Reader, Preview, etc.) and highlight as usual.

Alternatively, some PDF viewers (like PDF‑XChange Editor) have a “freehand highlighter” that draws over images – this is not true text highlighting but can simulate it for visual marking.

How do I search for highlighted text in a PDF?

Searching for highlighted text helps you quickly navigate to important passages. Methods vary by tool:

Adobe Acrobat Pro (or free Reader with Comments panel): Open the Comments panel (right sidebar). All highlights appear as entries. Click any highlight to jump to that location. You can also filter the panel by type (e.g., only Highlights). Pro version can export highlights to a separate document.
PDF‑XChange Editor: Open the Comments panel (left sidebar). Highlights are listed. Use the search box within the panel to find specific highlight text.
Adobe Acrobat Reader (free only): There is no direct “search highlights” feature, but you can use the regular search (Ctrl+F) and visually scan for yellow backgrounds.
Our online tool: Does not support searching highlights. Use the download feature and search in Adobe Reader or PDF‑XChange.

For advanced workflows, using Acrobat Pro or PDF‑XChange Editor is recommended if you need to frequently find or export highlights.

How do I highlight text on a PDF on my phone (Android/iPhone)?

Yes, you can highlight text in PDFs on mobile devices using free apps:

Adobe Acrobat Reader (free, iOS/Android): Open the PDF, tap and hold on a word to select it, then drag the selection handles to cover the desired text. Tap Highlight from the popup menu. To change color, tap the highlight, then the color palette icon.
Xodo PDF (free, iOS/Android): Open PDF, tap the highlight tool in the bottom toolbar, select color, then drag over text. Xodo also supports underline and strikethrough.
Microsoft Edge (mobile): Open PDF in Edge browser, tap the pen icon, choose highlighter, drag over text. Highlights are saved with the PDF.
Google Drive PDF viewer (limited): You can highlight in the Google Drive app, but highlights only work within the Drive environment and may not save to the original PDF. Better to use a dedicated app.

Mobile highlighting is convenient for on‑the‑go reading, but for heavy annotation, use a desktop application.

Are highlights permanent? Can I remove them later?

Highlights are not permanent by default. Most PDF tools save highlights as separate annotation layers, which can be removed or edited at any time. However, there are two scenarios where highlights become permanent:

Flattened PDF: If you print the PDF to a new PDF (using “Print to PDF”), all annotations including highlights become part of the page image and cannot be removed. This is useful for final distribution.
Digital signatures that lock the document: Some signed PDFs are certified to disallow any modifications, including removing highlights. In that case, you cannot delete highlights without breaking the signature.

In all normal cases, you can remove highlights by right‑clicking and selecting Delete. Always keep an unannotated backup if you think you might want to change highlights later.

What is the difference between highlight, underline, and strikethrough in PDF?

These three markup tools serve different purposes in document review:

Highlight: Adds a colored background behind text. Best for emphasizing important passages, flagging content for later reference, or drawing attention without implying a change.
Underline: Draws a line beneath text. Traditionally used to suggest additions or to indicate emphasis. In collaborative PDF review, underline often means “this should be kept” or “this is correct”.
Strikethrough: Draws a line through text. Universally used to suggest deletion. In proofreading, strikethrough shows that the marked text should be removed or replaced.

Most professional PDF tools (Adobe Acrobat Pro, PDF‑XChange) support all three. Free tools may only offer highlight. For a complete review workflow, use all three together: highlight for attention, underline for approval, strikethrough for deletion.