What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.

At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.

We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.

  • Profile Image

    Form's iframe height is constantly recalculated on iOS

    Asked by webstudent_suu on October 14, 2016 at 01:07 PM

    In Safari for iOS 10, the form on our page constantly recalculates its iframe height, causing the bottom of the page to jiggle up and down. It has happened on multiple iPhones. It does not happen on iOS 9. It does not happen on other form pages on our site (such as https://www.suu.edu/testing-center/testing-intake.html).

    I connected Safari for Mac to my iPhone so I could try to debug the issue. As far as I can tell, it comes down to the condition check `window.parent != window` on line 3608 of jotform.forms.js (the `iframeHeightCaller` function). This condition shows that `window.parent` IS equal to `window` when the issue is expressed. I have no idea why this happens.

    Please look into this and let me know if I can help debug this further.

    Thank you,

    Tyler Mumford
    Southern Utah University

    Page URL:

  • Profile Image
    JotForm Support

    Answered by Mike on October 14, 2016 at 03:52 PM

    Thank you for contacting us.

    Is this issue still happening? I do not have an iOS device to test this, but when I check with simulator app via https://www.browserstack.com your embedded form seems to be working properly.

  • Profile Image

    Answered by webstudent_suu on November 04, 2016 at 01:22 PM

    Yes, the issue is still happening. I accidentally created two posts for this issue; see https://www.jotform.com/answers/961337-Form-s-iframe-height-is-constantly-recalculated.

  • Profile Image
    JotForm Support

    Answered by Mike on November 04, 2016 at 04:04 PM

    Your second thread has been updated. Thank you.