How to change the font and size of Phone Number field's sublabel

  • D
    Donna
    Asked on April 19, 2026 at 4:16 AM

    Is there a way to update the font "please enter a valid phone number" to Arial 12pt?

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    John JotForm Support
    Replied on April 19, 2026 at 6:44 AM

    Hi Donna,

    Thanks for reaching out to Jotform Support. I checked for an account linked to the email you shared, but couldn’t find one. If you can share the link to the form you’re working on, we can take a closer look and give you a more tailored solution based on what you’re trying to do.

    Now, coming back to your question, you can easily change the font and size of a phone number field's sublabel by Injecting CSS Codes into your form. Let me walk you through it:

    1. First, copy this code:

    /*thread 37592821 - make phone sublabel arial and 12pt*/
    label[id$="_masked"] {
        font-size: 12pt !important;
        font-family: "Arial";
    }
    /*ends here*/

    2. In Form Builder, click on the Paint Roller icon on the right side of the page to open Form Designer.

    3. Now, in the Form Designer menu, click on the Styles tab, scroll down and paste the code into the Inject CSS Code box. That’s it. The code is automatically saved.

    How to change the font and size of Phone Number fields sublabel Image 1 Screenshot 30 Check out the screenshot below to see the results:

    How to change the font and size of Phone Number fields sublabel Image 2 Screenshot 41Give it a try and let us know how it goes.

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