How to Adjust Line Thickness in Adobe Acrobat with Apple Pencil
Question details
The user is looking to configure a custom, thinner line thickness for their Apple Pencil annotations in the Adobe Acrobat app on iOS.

- Product
- Adobe Acrobat for iOS
- Device & OS
- iOS
- Scenario
- Annotating and drawing on a PDF document using an Apple Pencil.
- Observed behavior
- The application only provides predefined stroke thickness options, and users cannot manually input or select a custom thickness beyond the built-in choices.
Ensure your Adobe Acrobat Reader app is updated to the latest version on your iPad and verify that your Apple Pencil is fully charged and actively paired.
Use Predefined Stroke Thickness Options
While a completely custom line thickness is not supported, you can ensure you are utilizing the thinnest predefined stroke available in the application.
Adobe Acrobat Reader for iOS currently limits Apple Pencil strokes to specific predefined thickness levels. You cannot type in a custom numerical value, but you can select the lowest available preset to minimize the width of your annotations.
Launch Adobe Acrobat Reader on your iPad, open your target PDF document, and tap the pencil icon to enter the commenting mode.
Tap the 'Draw' tool (pencil icon) located in the annotation toolbar at the bottom of the screen.
Tap the color and thickness indicator. From the pop-up menu, select the smallest circle icon to apply the thinnest predefined stroke setting to your Apple Pencil.

Annotate PDFs with Precision Using WPS Office
If predefined options are too limiting for your workflow, WPS Office provides a robust PDF editor that offers highly flexible and precise annotation tools, perfectly capturing your Apple Pencil strokes exactly how you want them.
- 1. Open your PDF Document: Launch WPS Office on your iPad and open the PDF file you wish to edit and annotate.
- 2. Access Annotation Tools: Navigate to the top menu bar and select the 'Annotation' or 'Edit' tab to reveal the drawing toolset.
- 3. Customize Pen Thickness: Select the Pen tool and tap the settings icon to fine-tune your exact desired line thickness for the Apple Pencil.
- 4. Start Drawing: Begin writing or drawing on your document. Your precise custom stroke settings will be smoothly applied.

Frequently Asked Questions
Can I use third-party plugins to get custom line thickness in Acrobat for iOS?
No, Adobe Acrobat Reader for iOS is a closed environment and does not support third-party plugins that alter native tool behaviors such as Apple Pencil stroke settings.
Does pressure sensitivity affect line thickness in Adobe Acrobat for iPad?
Adobe Acrobat offers some basic pressure sensitivity support for the Apple Pencil, but your baseline stroke thickness is heavily restricted by the predefined size preset you have currently selected.
Is custom line thickness available in the desktop version of Adobe Acrobat?
Yes, unlike the iOS mobile app, the desktop versions of Adobe Acrobat Pro and Standard provide comprehensive properties for drawing tools, allowing you to set highly specific numerical line thickness values.




