EDIT PDF
Free Underline Text online
Add underlined text to PDF.
Underline Text is a free browser tool that lets you add underlined text to PDF. Drop your text into Underline Text, choose your settings, and save the finished file. Underline Text works on your device only, so no file or text is ever uploaded.
- Free to use
- No signup
- No uploads
- Works offline
Why use Underline Text
- add underlined text to PDF without installing software
- Your text is processed on your device by Underline Text, never uploaded
- Underline Text needs no account, email address or payment details
- Underline Text is batch-friendly: reuse it immediately on the next file
- Underline Text is keyboard accessible and screen-reader friendly
- Underline Text is free forever, with no watermark on the result
Underline Text runs entirely inside your browser. Your text is never uploaded, stored or shared, and nothing is retained once you close the tab.
How to use Underline Text
- Add your text Drag your text onto the drop zone or pick it from your device.
- Adjust the options Set the options that control how Underline Text handles your input.
- Run the tool Underline Text works instantly on your device, with no queue and no upload wait.
- Download the result Save the finished file straight to your device, then reuse the tool as often as you like.
Benefits
Private by design
Your text stays on your device while Underline Text works. Underline Text never sends it to a server, so confidential work stays confidential.
Instant results
Underline Text finishes most jobs in under a second because the work happens on your own hardware.
No signup, no limits
Use Underline Text as many times as you want. Underline Text asks for no account, adds no watermark and keeps no paid tier gating the output.
Works offline
Once the page has loaded, Underline Text keeps working without a connection, which helps on flights and locked-down networks.
Who it is for
For students
Students use Underline Text to hand in coursework without installing software: add underlined text to PDF on a shared or locked-down machine.
For freelancers
Underline Text helps freelancers send client deliverables quickly, since your text never leaves the laptop it was created on.
For HR and admin teams
Underline Text helps HR and admin teams process paperwork quickly, since your text never leaves the laptop it was created on.
How it works
Underline Text loads your text into memory, applies the change you requested to the underlying data rather than to a screenshot of it, and writes a fresh copy for download. Your original stays untouched on disk, and every step of Underline Text happens inside your browser sandbox.
Frequently asked questions
Is Underline Text free to use?
Yes. Underline Text is completely free with no account, no trial and no usage cap. Every feature on this page is available on the first visit.
Does Underline Text upload your text to a server?
No. Underline Text processes your text inside your browser, so it never reaches a DocTools server. That also means the tool keeps working if your connection drops mid-task.
Is there a file size limit?
The practical ceiling is your device's available memory rather than a server quota. Files up to roughly 100 MB work comfortably on a typical laptop in Underline Text.
Do I need to install anything to use Underline Text?
No installation is needed. Underline Text runs in Chrome, Edge, Firefox and Safari, on desktop and on mobile, with no extension or plugin.
Can I use Underline Text on a phone or tablet?
Yes. The Underline Text interface adapts to small screens and supports touch input, though very large jobs are faster on a desktop browser.
What happens to your text when I close the tab?
It is discarded. Underline Text keeps everything in temporary browser memory, so closing the tab removes every trace of the session.
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- Add Watermark | Stamp text across every page of your PDFs
- Edit PDF | Edit text and images in your PDF
Last updated: 2026-09-07