How to Create a Comb Field for Phone Numbers in Adobe Acrobat
Question details
The user needs to format a PDF form text field as a comb field to separate entered phone number characters into individual, fixed-length boxes.

- Product
- Adobe Acrobat
- Device & OS
- not provided
- Scenario
- Creating or modifying a fillable PDF form where fixed-length inputs like phone numbers require individual cell formatting.
- Observed behavior
- The user needs to configure text fields so that digits are divided into separate cells, noting that standard character limits conflict with the comb option.
Ensure your PDF document is open in form editing mode and that you know the exact digit groupings required for your phone number format, such as a 3-digit area code followed by a 3-digit and 4-digit segment.
Configure Comb Options in Text Field Properties
Use the Options tab within the text field properties to enable the comb feature and specify the exact number of cells for the phone number segments.
A comb field automatically separates entered characters into individual boxes, which is perfect for fixed-length data like phone numbers or identification codes.
In Adobe Acrobat, the 'Comb' option and the standard 'Limit of characters' option are mutually exclusive because both attempt to restrict the character count. You must disable the standard character limit before applying the comb layout.
Right-click the designated text field for your phone number and select 'Properties' from the context menu.
In the Text Field Properties dialog box, click on the 'Options' tab at the top.
Ensure that the 'Limit of [ ] characters' checkbox is unchecked. If it is checked, the Comb option will be grayed out or unavailable.
Check the box next to 'Comb of [ ] characters'. Enter the specific number of cells needed for this segment (for example, type '3' for an area code).
Click 'Close' to save the settings. Repeat this entire process for the remaining parts of the phone number, creating separate comb fields for the 3-digit prefix and 4-digit line number.

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WPS Office offers a comprehensive suite of PDF tools that make creating, editing, and filling out interactive forms effortless. It's a fantastic, lightweight alternative for all your document formatting needs.
- 1. Open Your PDF: Launch WPS Office and open your existing PDF form or create a new blank document.
- 2. Access Form Tools: Navigate to the 'Form' tab on the top ribbon to access the interactive form controls.
- 3. Insert Text Fields: Click on 'Text Field' and draw the field directly onto your document where the user input is required.
- 4. Customize Properties: Double-click the newly created text field to open its properties, where you can adjust alignment, font size, and text limits to suit your form's needs.

Frequently Asked Questions
Why is the Comb option grayed out in Acrobat?
The Comb option is only available when the 'Scroll long text' option is unchecked and standard character limits are disabled. It also requires the field to use standard fonts without Rich Text formatting enabled.
Can I use the Comb feature for dates or Social Security Numbers?
Yes, comb fields are ideal for any fixed-length data entries such as Social Security Numbers, dates, or ID numbers, as they force the user to enter exactly one character per designated box.
How do I align the text inside a comb field properly?
In the Text Field Properties menu, under the Options tab, look for the 'Alignment' dropdown. Setting it to 'Center' usually ensures that the characters sit perfectly within their respective boxes.




