Kit + ListDefender
Protect your sender reputation, clean your subscriber list, and block fake sign-ups with ListDefender’s email hygiene and form protection tools - all built for Kit users.
With the Kit + ListDefender integration, you can:
Clean your subscriber list automatically. ListDefender scans your Kit contacts and tags them as Green (safe to send), Yellow (re-engage), or Red (do not send) so you always know who to email.
Block bots and fake sign-ups. FormDefender validates form submissions in real time, catching spam, disposable emails, and known bad actors before they reach your list.
Monitor engagement continuously. ListDefender tracks subscriber engagement over time and automatically updates tags when contacts become disengaged, so you can act before deliverability drops.
Automate list hygiene with Visual Automations. Use ListDefender tags to trigger Kit automations that unsubscribe risky contacts, re-engage slipping subscribers, or route new sign-ups through validation holds.
Getting started with ListDefender
To use the Kit + ListDefender integration, you need to:
Have an active Kit account (any plan)
Have a ListDefender account (create one at listdefender.app/register)
Know your Kit API Key and API Secret
Connect ListDefender to Kit
Log in to your ListDefender account at listdefender.app (or create an account if you don’t already have one)
Click Connect your EMP now and choose Kit
Enter your Kit login credentials and grant access to ListDefender
Click Save to save your credentials and close the window
Configure your ListDefender settings, including quality checks and engagement monitoring, new subscriber, and other preferences
Enter payment details and continue
Click here to see the help article on how to use FormDefender on your Kit Landing Page
The integration is now active. ListDefender will begin processing your data. Results will appear in your ListDefender account when the scan ends. Simultaneously, your subscriber records in Kit will be updated with results of the scan(s), including tags being set and, if configured, custom fields being added with values. Depending on the size of the subscriber list, it could be several minutes to several hours. Progress will be shown on the dashboard during the scan (the scan will continue if you close your browser window or tab). Once the initial scan is complete, ListDefender will send an email with your results (also available on your ListDefender dashboard).
ListDefender also offers a form-protection-only version called Essentials. If you only need FormDefender to protect your Kit forms from fake sign-ups, Essentials is available at $25/month for unlimited forms and submissions. Visit listdefender.com/pricing for details. |
How to use the ListDefender app
Tags
ListDefender automatically creates and manages tags on your Kit subscribers. All tags are prefixed with “ListDefender:” and can be viewed inside the ListDefender application. The tags ListDefender creates are shown below.
Tag name | Type | Description |
ListDefender: Status = Green (Send Responsibly) | Status | Contact is safe to email |
ListDefender: Status = Red (Do Not Send) | Status | Contact is not safe to email |
ListDefender: Status = Yellow (Re-Engage) | Status | Contact should be re-engaged |
ListDefender: Quality Check = Is Tag | Quality | Address contains a tag (e.g., [email protected]) |
ListDefender: Quality Check = Is Free | Quality | Address is from a free provider (e.g., Gmail, Yahoo) |
Default tags created by ListDefender:
“ListDefender: Status = Green (Send Responsibly)” Tag: Applied to subscribers that are safe to email. These contacts have valid, deliverable addresses and show healthy engagement.
“ListDefender: Status = Red (Do Not Send)” Tag: Applied to subscribers that should not be emailed. These contacts have invalid addresses, are spam traps, or have other deliverability risks.
“ListDefender: Status = Yellow (Re-Engage)” Tag: Applied to subscribers showing signs of disengagement. Consider running a re-engagement campaign before continuing to email these contacts.
“ListDefender: Quality Check = Is Tag” Tag: Applied when an email address contains a tag (e.g., [email protected]). This can indicate a test address or someone deliberately segmenting their inbox.
“ListDefender: Quality Check = Is Free” Tag: Applied when an email address uses a free email provider (e.g., Gmail, Yahoo, Outlook).
Use FormDefender to protect your Kit forms
After creating your ListDefender account and submitting payment details, you can set up advanced form protection with FormDefender. FormDefender validates form submissions in real time, blocking bots, disposable emails, and other fake sign-ups before they reach your Kit subscriber list.
In your ListDefender account, navigate to the left side menu and select FormDefender
Edit the “default” configuration or create a new configuration. (A configuration can be used on one or more of your forms).
Configure your protection settings (choose which submission types to block, such as detected bots, abusive IPs, disposable email addresses, and more)
If you are using a Kit form, select Kit Forms, from the dropdown. For Kit forms being embedded on a page do NOT add the snippet as a “Script” element inside your Kit form. Instead, add it to the HTML of the page where you are placing this form.
5. Test your form by submitting a few entries to ensure FormDefender is working
properly
FormDefender is available in both ListDefender Complete and ListDefender Essentials. If you only need form protection without full list cleaning and engagement monitoring, you can use ListDefender Essentials for only $25/month. |
Use ListDefender data in Kit
Once ListDefender is connected, you can use the tags it pushes to Kit to trigger Visual Automations, create segments, and improve your email targeting and deliverability.
Set up automations based on ListDefender tags
Once you have the ListDefender app installed, you’ll be able to use the tags from the ongoing sync to trigger automations in Kit. Here are some examples:
Automatically unsubscribe or suppress contacts tagged as Red (Do Not Send)
Route new form submissions through a validation hold before entering a welcome sequence
Send an internal notification when slippage monitoring detects engagement drops
Trigger a re-engagement sequence for subscribers tagged as Yellow (Re-Engage)
Here’s how to set up a ListDefender automation:
Go to Visual Automations under the Automate tab in the navigation. Click the + New automation button
Click Start from scratch
Select Tag as your entry point trigger
Choose the ListDefender tag you want to trigger the automation (e.g., “ListDefender: Status = Red (Do Not Send)”)
Add your desired actions (unsubscribe from a sequence, add to a segment, send a notification, etc.)
Segments
Use the Segment Builder in Kit to create segments based on ListDefender tags. For example, create a segment of all subscribers tagged as “Green” to ensure your broadcasts only reach verified, engaged email addresses, or segment contacts flagged for re-engagement to run targeted campaigns.
Disconnect ListDefender from Kit
By default, canceling your ListDefender account will remove the connection between ListDefender and Kit. No further action is needed. Tags that were previously applied to your Kit subscribers will remain unless you manually remove them.
ListDefender troubleshooting
I connected ListDefender but don’t see tags on my subscribers
Make sure the initial scan has completed. Check your ListDefender dashboard for scan progress.
Verify that your Kit API Key and API Secret are correct and have not been reset.
If there are ever issues, notifications will be emailed to you and displayed inside the ListDefender application alerting you that settings need to be updated.
Form protection not working
Double check that you selected the correct platform (Kit) from the FormDefender Get Code dropdown.
Verify that the code snippet was copied and pasted exactly as shown.
If you are using a non-supported form platform and wanting to use FormDefender, reach out to support and ask about possible workarounds.
My tags aren’t being applied correctly
Verify that the subscriber exists in your Kit account and has a valid email address.
Check the ListDefender dashboard for any scan errors or processing issues.
If the issue persists, reach out to ListDefender support
Frequently asked questions
Does ListDefender cost extra?
Yes, ListDefender is a separate paid service. ListDefender Complete starts at $20/month based on your list size and includes full list cleaning, engagement monitoring, and FormDefender. ListDefender Essentials is available at $25/month for form protection only (unlimited forms & new subscribers). Visit listdefender.com/pricing for current pricing.
Which Kit plans does ListDefender work with?
ListDefender works with all Kit plans. There are no Kit plan restrictions for using the integration.
How often does ListDefender scan my list?
ListDefender continuously monitors your subscriber list. After the initial scan, it processes new subscribers as they’re added and periodically re-evaluates existing contacts for engagement changes.
Will ListDefender automatically unsubscribe contacts?
No. ListDefender only applies tags to your subscribers. It’s up to you to decide what actions to take based on those tags. You can set up Visual Automations in Kit to automatically unsubscribe contacts tagged as Red, or take any other action you choose.
What happens to ListDefender tags if I cancel?
Tags that were previously applied to your Kit subscribers will remain in place after cancellation. ListDefender will stop updating tags, but existing tags won’t be removed unless you manually delete them.
Can I use ListDefender with Kit’s Creator Network?
Yes. ListDefender works with all subscribers in your Kit account regardless of how they were acquired, including through the Creator Network, landing pages, or API imports.
Get help
For questions about the ListDefender integration:
Email: [email protected]
Documentation: ListDefender Help Center
Website: listdefender.com