Do you want to block submissions from your Webflow forms to gmail addresses, hotmail, or Yahoo because the leads are unqualified?
In this tutorial, you will learn how to create a list of email domain names that will be blocked when submitting your Webflow forms.
Prefer videos? Watch our French tutorial on YouTube!
Using Finsweet's Hack #18 for Webflow
Finsweet's hack 18 will allow you, in just three simple steps, to add this feature (with JavaScript code) to any Webflow site. This solution does not require any additional tools and is 100% free. Thank you, Finsweet 🙌
1. Copy and paste the code into your site
To use this technique, you must copy and paste the JavaScript code below into the "before "
tag" of the Webflow page containing the form for which you wish to block non-business emails.
<!-- F’in sweet Webflow Hacks -->
<script>
// when the DOM is ready
$(document).ready(function() {
// make an array of invalid domains
const invalidDomains = ['gmail.com', 'AJOUTER-ICI', 'hotmail.com', 'competitor.com'];
// get the submit button
const submitBtn = $('.hack-button');
// on submit button click
submitBtn.click(()=>{
// get the email field
const email = $('.hack18-email');
// split email at '@' character to get domain
const domainPart = email.val().split('@')[1];
// if the domain exists in the invalidDomains array
if(invalidDomains.indexOf(domainPart) !== -1) {
// clear email field
email.val('');
// add a 'use business mail' placeholder
email.attr('placeholder','Please enter a business email');
// prevent form submission
return false;
}
else{ // else if email is not invalid
// submit form
return true;
}
});
});
</script>2. Customize the code
Next, you need to customize the code to decide which email addresses you want to block. Gmail address? Or for example, the email address of your competitors who might be looking to access your free content?
On the line "const invalidDomains = [ 'ADD-HERE'];" replace the value ADD-HERE with the root of the email address you wish to exclude.
If you want to exclude emails coming from Google addresses, simply replace "ADD-HERE" with "gmail.com".
Bonus: Customize the placeholder message of your Webflow form
In the JS code, replace the phrase "Please enter a business email" with your desired message. For example: "Professional email address"
That’s it, you now know how to prevent the submission of your Webflow forms from any email address.


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