MailboxValidator vs NeverBounce

MailboxValidator checks email addresses and mailboxes to flag invalid addresses and help reduce email bounces. It is available on the web and through an API, with single-address results returned as JSON or XML. For lists, users can upload text or CSV files for bulk validation. Checks cover syntax, MX records, SMTP responses, greylisting, disposable and free-provider addresses, role addresses, suppression, DMARC, strict SPF, and website reachability. The company says it tests the connection through the SMTP server without sending a message to the recipient. Listed integrations include Zapier, Make, MailChimp, Mailgun, SendGrid, HubSpot, and others; API documentation links libraries for Node.js, Ruby, PHP, Perl, Python, Java,.NET, Go, and Rust. The free API plan is free, billed per month, with 300 queries and 30-day validity. A bulk trial is free for 100 queries and 30-day validity. Yahoo validations are unsupported, and non-ASCII addresses are marked invalid syntax. The FAQ says refunds are not offered; its privacy policy says processed personal data is retained indefinitely, subject to policy limits on deletion requests.

NeverBounce has no write-up on Specifiction yet; its figures are above.