Must Be a Valid Email Address: Format Rules and Examples
The rules for a valid email address format: local part, @, domain, length limits, allowed characters, invalid examples and why forms reject yours.
How to check whether an email address is real before you send to it: the format rules, catch-all and disposable addresses, checks at sign-up, the validation API and integrations, and finding the right address in the first place.
14 articles
The rules for a valid email address format: local part, @, domain, length limits, allowed characters, invalid examples and why forms reject yours.
Learn the common company email formats, how to find a company's pattern from public sources, and how to check a guessed address before you send.
How CampaignKit's disposable email checker works, what the disposable flag and score mean, and how to block throwaway signups with the API.
Learn how to integrate real-time email validation into signup forms, checkout pages, and registration flows to prevent bad data from entering your system.
A catch-all email domain accepts mail for any address. Learn how to tell if a domain is catch-all and what to do with catch-all results.
Avoid email bounces, protect your sender reputation, and improve deliverability. This guide breaks down how and why to verify email addresses.
Learn how email validation works with examples and simple techniques. Discover best practices to improve deliverability and protect your email list.
How email verification supports GDPR compliance, plus a checklist for hosting, DPA and data retention when picking a vendor.
Improve email deliverability and reduce bounce rates with CampaignKit. Clean your list, verify addresses, and boost campaign performance.
Learn how to check if an email is valid: manual checks, what verification actually tests, and a free instant checker with no signup required.
Write an Auth0 Pre User Registration Action that validates sign-up emails and blocks disposable, invalid and blacklisted addresses. Code included.
You're a marketing manager and you convinced your customer to start taking email marketing seriously. The client collected thousands of email addresses of…
Enhanced email validation for FluentCRM.
The Email Validation API allows you to validate a list of email addresses and to retrieve detailed validation results.