Real-time email validation on sign-up forms: how it works and what it catches
Real-time email validation checks an address as it is typed: syntax, typos, disposable domains, role accounts, MX and an optional mailbox check. Here is how it works.
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Deliverability, explained.
Guides and research on email verification, bounce rates, catch-all domains, disposable addresses, list hygiene and sender reputation. Written by the people who run the engine.
13 posts tagged guides
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@Sender reputation in 2026: what the Gmail and Yahoo bulk sender rules mean for you
Sender reputation explained: what Gmail and Yahoo measure, the February 2024 bulk sender rules one by one, how bounces and complaints feed it, and a 30-day recovery plan.
@How to clean a Klaviyo list before your next flow
Clean a Klaviyo list the right way: export and verify, suppress undeliverable profiles, build a verified-deliverable segment, and keep sign-up forms clean with real-time checks.
@How to verify emails in Google Sheets: three methods compared
Three ways to verify emails in Google Sheets compared, then a full Apps Script custom function with caching, the formulas to use it, formatting tips and when to switch to a bulk job.
@How to clean a Mailchimp audience (without losing good contacts)
Two safe ways to clean a Mailchimp audience: export, verify and re-import with update existing contacts, or connect Verifyre to tag and unsubscribe undeliverable addresses.
@How to clean an ActiveCampaign list with tags and automations
How to clean an ActiveCampaign list: verify contacts, tag them by verdict, and let automations unsubscribe dead contacts and re-confirm risky ones. Steps, a CSV alternative and a verdict table.
@The email list hygiene checklist for 2026
A ten-step email list hygiene checklist: verify at capture, clean before big sends, drop role and disposable addresses, sunset the unengaged and keep your bounce rate under 2%.
@How to clean a Brevo contact list before your next campaign
How to clean a Brevo contact list: connect with an API key, verify the list, write results to an attribute, move dead contacts to a suppression list or blocklist, and know when to re-run it.
@What is email verification and how does SMTP verification work?
Email verification checks whether an address can really receive mail. We walk through syntax, MX, reputation lists, the SMTP handshake, catch-all probes and scoring.
@Email list decay: how fast do email lists go bad and what to do
Email lists typically lose 22% to 30% of their valid addresses every year. What drives decay, what it does to a 10,000-contact list, how to measure your own rate and how often to re-verify.
@How to clean a HubSpot contact list: verify, tag and suppress
A step-by-step guide to cleaning a HubSpot contact list: build the list, verify it through the integration, write the verdict to a custom property, then suppress and set undeliverable contacts to non-marketing.
@Email verification API: what it is and how to integrate one
An email verification API checks an address over SMTP and returns a verdict your code can act on. Here is the request, the JSON response, and working examples in curl, Node.js and Python.
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