Email Validation

Email Validation in Ultimate Spin Wheel

A spin wheel is only as valuable as the leads it captures. If your list fills up with throwaway addresses, your open rates fall and your coupons go to people who will never return. Ultimate Spin Wheel protects your list in two ways: it validates the format of every email on the server, and it can block disposable (temporary) email providers before the spin is recorded. Both checks run in the free plugin.

Key facts:

1. Format is validated on the server. Every submitted email is checked with WordPress’s own is_email() function, so a badly formed address is rejected even if a visitor edits the form in their browser.
2. Disposable-email blocking is optional and free. When enabled in the Security settings, addresses from known temporary-mail providers are refused with a message you control.
3. The block list is local. The plugin ships a bundled list of 100+ known disposable domains (Mailinator, Guerrilla Mail, 10MinuteMail, and similar). No external API call is made, so there is nothing to slow down the spin.
4. No MX/DNS lookups are performed. Validation is syntax plus domain-blocklist only — the plugin does not ping mail servers or DNS records.

1. Format Validation (Always On)

When a visitor submits the lead form and spins, the server checks the email before saving anything:

• The value is sanitized with sanitize_email() and then validated with WordPress’s is_email().
• If the address is not a valid format, the spin is refused with “Please enter a valid email address.”
• This runs server-side, so it cannot be bypassed by disabling client-side checks. If the email field is required in your form settings, an empty value is rejected too.

Format validation confirms that an address is well-formed (it has a local part, an @, and a domain). It does not confirm that the mailbox actually exists — that is what disposable-email blocking helps with next.

2. Disposable Email Blocking

Temporary-mail services (Mailinator, Guerrilla Mail, 10MinuteMail, and dozens of others) let a visitor grab a coupon with a throwaway inbox they never check. Disposable Email Blocking stops those sign-ups.

• How it works: the plugin extracts the domain from the submitted email and compares it against a bundled list of 100+ known disposable providers. A match refuses the spin; anything else passes.
• Custom message: blocked visitors see the message you set (default: “Please use a valid, non-temporary email address.”).
• Server-enforced: the check runs during the spin request, so no lead is stored and no coupon is issued to a disposable address.

Turning It On

1. Go to Spin Wheel → Settings and open the Security tab.
2. Scroll to Disposable Email Blocking and toggle it on. The status badge switches to Active.
3. Optionally, type a custom rejection message in the field that appears.
4. Save the settings. The rule applies to every campaign immediately, since it is a global setting.

Why It Matters

• Cleaner lists: a smaller list of real people is worth far more than a large list of inboxes nobody reads.
• Better deliverability: sending to addresses that never open mail hurts your sender reputation over time. Filtering junk at the point of entry helps keep bounce and complaint rates low.
• Less coupon abuse: combined with IP and device blocking, it makes it harder to farm coupons with an endless supply of throwaway inboxes.

Frequently Asked Questions

Does the plugin verify MX records or ping the mail server?

No. Validation is limited to email format (via WordPress’s is_email()) plus a check of the domain against a local disposable-provider list. There are no DNS or MX lookups, so a mistyped-but-valid-looking domain such as gmil.com will still pass.

Will this slow down the spin?

No. The block list is bundled with the plugin and checked in memory. There is no external API request, so the added time is negligible.

Is there a “Did you mean?” typo suggestion or a Strict/Loose mode?

No. Those are not part of the plugin. There is a single on/off toggle for disposable-email blocking plus the always-on format check. You do not choose a strictness level.

Can I add my own domains to the block list?

The disposable list is bundled with the plugin and is not editable from the settings screen. If a specific abuser is a problem, use the manual IP or device blocking on the Security tab instead.

Is disposable-email blocking a Pro feature?

No. Both format validation and disposable-email blocking work in the free plugin. Email-marketing integrations (Mailchimp, Klaviyo, and others) that sync those cleaned leads onward are Pro.

Related Documentation

• Global Settings: The Security, Email, Integrations, and General tabs that apply across every campaign.
• Win Probabilities: How winners are drawn securely on the server.

Conclusion

Ultimate Spin Wheel keeps your lead list clean with a server-side format check on every email plus an optional, free block on disposable providers. Enable Disposable Email Blocking on the Security tab, set a friendly rejection message, and let real addresses through while the throwaways bounce off. For help, visit the wowDevs support center.