Last updated on
Sep 19, 2025
Underline In PDF Online For Free
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What our customers say about pdfFiller
See for yourself by reading reviews on the most popular resources:
The software in simple & I love it: however the video for how to: tells you what the form is used for; not how your software works. (I think that people already know what the 1099 int is used for)
2015-02-05
I had an issue that customer service…
I had an issue that customer service handled quickly and professionally. I was very impressed! I highly recommend working with this company they have excellent customer service.
2020-01-17
Awesome Product
The software is very user friendly. It's a great value for the cost. Makes my life so much easier
None so far. The software is pretty awesome
2019-10-01
A "Must have" business software.
I am a partner in a CPA firm. We regularly receive emails loaded with "pdf" attachments. It's a pain to open and print each one. PDFiller makes the process as simple as can be.
Simple to use. You literally drag all your "pdf" files into PDFiller and hit the merge key. Works like a charm, every time.
Really can't think of anything that I don't like about the software.
2019-05-16
Great Product!
I love this software; it has been invaluable. I have used it to fill out job applications, insurance, medical & school documents. I'll continue to use it.
It is very easy to upload documents to this software. Editing is user-friendly even for those not technically savvy. I like that I have many options in saving or exporting my finished document. Also, I like that my previous documents are saved because there has been more than once that a document has been lost or needed again. I have been saved by the fact that PDF Filler has the previously used document saved.
I have not found anything I really dislike about this software. I'll be honest in that I'm not crazy about the price but I have found this software so helpful I have been using it for over two years now. I've recommended it to several people. I did not rate the customer service because I have never used it. I guess the fact that I've been using this for over two years & never had a customer service issue speaks for itself.
2019-05-16
This was easy to work with and understand, now I can get my work done
This was easy to work with, so simple to understand.
converting files was a nightmare, now it's all working so well.
2024-05-27
I seek clarification about the 30 days free trial.
I seek clarification about the 30 days free trial of using the services. The reply was prompt, direct helpful and highly satisfactory.
2023-12-07
I love Pdf Filler. I have tried ten different products similar to Pdf Filler and none of them had the features, functionality, utility, intuitive interface, and price point. I tried ADOBE and absolutely hated every moment. I cannot tell you how happy I am with your product!!! We have streamlined our HR onboarding process and our clinician credentialing process. Thank you!
2021-05-12
What do you like best?
Easy to use. Very little start up time. Comprehensive set of features
What do you dislike?
Being in the cloud does require upload and download steps
What problems are you solving with the product? What benefits have you realized?
I use it daily for contacts and client documents
2020-11-18
Instructions and Help about Underline In PDF Online For Free
Did you ever need to underline or cross out text in PDF documents?
To get started, upload a document to your account and open it in the editor. To draw a line, click the Line icon in the main toolbar. The line toolbar will appear under the editing tools. Click where you want to create the start point and drag to where you want to create the end point, release the mouse button and click OK.
To change the line’s color, click on the black square and choose the color you want. Use the slider before or after drawing a line to change its thickness. You can change the position of the line ends by dragging them. Finally, you can always delete any line you've drawn, just select it and click the trash can icon that will appear.
In the past, you probably had to print the document, underline words or phrases with a pen, and either scan the document or send a hard copy to wherever it needed to go. Besides needing a printer and a scanner, the process probably took you far too much time to complete.
Now there is a far easier way to underline text in PDF documents. You can simply use pdfFiller!
To learn more about drawing lines in PDF documents online, please watch the following video:
When you use pdfFiller to underline text in PDF documents, you do not use paper, pencils, fax, and printer. And even better, you save yourself a lot of time! If you like being able to underline text in PDF documents online, you might be interested in a lot of other great features that pdfFiller has to offer including highlighting and erasing content, adding pictures, text boxes and sticky notes, and creating fillable fields. Check out these tutorials to see the other great things that pdfFiller can do for you!
01
To underline content in a PDF, upload your PDF document using pdfFiller's uploader.
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Choose the 'Line' button in the 'Tools' tab and draw a line. You can drag and move the line anywhere in your document.
03
You can also click the 'Tools' tab and highlight, redact or erase text and images in your PDF.
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When you're done with editing, click the 'Done' button and email, print or save your document.
Underline In PDF Feature
Welcome to our new Underline In PDF feature, designed to make your PDF editing experience even better!
Key Features:
Easily underline text in your PDF documents
Choose from a variety of colors and thickness for the underline
Undo and redo options for precise editing
Potential Use Cases and Benefits:
Highlight important information in reports and presentations
Mark key points in study materials for quick reference
Annotate documents for collaboration and feedback
With our Underline In PDF feature, you can effortlessly emphasize crucial details and enhance the readability of your documents. Say goodbye to the hassle of printing and manually underlining text - streamline your workflow and impress your audience with clear and impactful PDFs!
How to Use the Underline In PDF Feature
The Underline In PDF feature in pdfFiller allows you to easily underline text in your PDF documents. Follow these simple steps to use this feature:
01
Open the PDF document you want to edit in pdfFiller.
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Click on the 'Text' button in the toolbar at the top of the page.
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Select the text you want to underline by clicking and dragging your cursor over it.
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Once the text is selected, a formatting toolbar will appear above it.
05
Click on the 'Underline' button in the formatting toolbar.
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The selected text will now be underlined.
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To remove the underline, simply click on the 'Underline' button again.
That's it! You have successfully used the Underline In PDF feature in pdfFiller. Enjoy editing your PDF documents with ease!
For pdfFiller’s FAQs
Below is a list of the most common customer questions. If you can’t find an answer to your question, please don’t hesitate to reach out to us.
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What is pdfFiller?
pdfFiller is a web-based PDF editor. With pdfFiller, you can search for, edit, store and export PDF documents online without downloading and installing any software. pdfFiller also allows you to access and modify your PDF documents from any device anytime.
What browsers do pdfFiller.com support?
pdfFiller.com supports Internet Exporter (IE), Google Chrome, and Mozilla Firefox.
Do I need to download or install any software?
No downloads needed! pdfFiller.com is web-based application that does not need any additional software. pdfFiller.com supports any browser.
Can I edit a PDF document online?
Yes. pdfFiller.com allows you to edit (modify, alter, correct, change, amend, revise, redact) any document with our various tools and features. You can rearrange, rotate, and delete, the pages. You can also, add text, images, and signatures to each page.
How to annotate PDFs?
To annotate PDF documents, upload your document to pdfFiller, or choose the document your want to annotate in “My Forms” page and click “Fill” button. Open “Draw” tab and access the editor toolbar, you can have a variety of annotation features: highlight text, add comments, underline text and insert sticky notes or arrows.
How to underline in PDF?
To underline in PDF documents, upload your PDF documents to pdfFiller, or choose the PDF you'd like to annotate in “My Forms” page and click “Fill” button on the right. You can find the “Line” button in “Tools” tab. Select the area or sentence you'd like to underline by clicking and holding the button on the mouse to draw a line around. Release the mouse when you're done. You can change the size of the line using the editor toolbar.
Can I underline into PDF?
Yes, you can insert multiple lines into PDF documents using pdfFiller. To underline into PDF documents, upload your PDF documents to pdfFiller, or choose the PDF you'd like to annotate in “My Forms” page and click “Fill” button on the right. You can find the “Line” button in “Tools” tab. Select the area or sentence you'd like to underline by clicking and holding the button on the mouse to draw a line around. Release the mouse when you're done. You can change the size of the line using the editor toolbar.
How to underline text in PDF certificate form?
To underline text in PDF forms, upload your PDF documents to pdfFiller, or choose the PDF you'd like to annotate in “My Forms” page and click “Fill” button on the right. You can find the “Line” button in “Tools” tab. Select the area or sentence you'd like to underline by clicking and holding the button on the mouse to draw a line around. Release the mouse when you're done. You can change the size of the line using the editor toolbar.
What PDF editor can draw a line to PDF forms?
pdfFiller can help you draw a line to any PDF document online. To draw lines in PDF documents, upload your PDF documents to pdfFiller, or choose the PDF you'd like to annotate in “My Forms” page and click “Fill” button on the right. You can find the “Line” button in “Tools” tab. Select the area or sentence you'd like to draw lines by clicking and holding the button on the mouse to draw a line around. Release the mouse when you're done. You can change the size of the line using the editor toolbar.
How do I write on a document?
To write on a document, click anywhere on the document and begin typing.
Can I type multiple lines when I have a lot of text?
Yes. Just use “Enter” to create a line break. You can also paste large chunks of text and use Enter to restructure the lines.
How do I edit font settings?
To edit font settings, begin by clicking on the “Font” button. You can then change the font type, adjust the size and color. Furthermore, you can also, modify text in to bold, underline, and italics.
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