Abstract Email Validation API vs MailboxValidator
Abstract Email Validation API
abstractapi.com
MailboxValidator
mailboxvalidator.comSide by side
| Figure | Abstract Email Validation API | MailboxValidator |
|---|---|---|
| Price from | $17/mo | Free |
| Free plan | — | Yes |
| Free trial | — | Yes |
| Open source | — | — |
| Web | Yes | Yes |
| API | Yes | Yes |
| Plans published | 5 | 10 |
| Spec score · Email Verification APIs | 7.8 (#13) | 7.9 (#12) |
| Bulk validation | The API supports bulk email validation and CSV upload is included on paid plans listed on the page. | Users can upload an email list in text or CSV format for bulk validation. |
| Integrations | The maker lists integrations including HubSpot, AWS, Salesforce, Zapier, Snowflake, Shopify, Make, Mailchimp, and Azure. | Listed integrations include Zapier, Make, MailChimp, AWeber, Mailgun, SendGrid, Campaign Monitor, SparkPost, HubSpot, MailerLite, Constant Contact, VerticalResponse, MooSend, Mailjet, iContact, ActiveCampaign, Intercom, Autopilot, ChatGPT, and MCP. |
| Purpose | The API checks whether an email address is real and can receive mail when a user submits it. | MailboxValidator checks email addresses and mailboxes to identify invalid addresses and help reduce email bounces. |
| Support | The product page says questions are usually answered by a real person within a few hours via email or [email protected]. | The privacy policy lists [email protected] and says to allow up to four weeks for a reply to privacy inquiries. |
| Validation checks | One call checks address format, domain MX records, live SMTP without sending a message, and disposable or catch-all addresses. | Checks include syntax, MX records, SMTP response, greylisting, disposable addresses, free providers, role addresses, suppression, DMARC, strict SPF, and website reachability. |
Plans
Abstract Email Validation API
- Starter$17 a month
- Standard$37 a month
- Professional$39 a month
- EnterprisePriced on request
- FreePrice not published
MailboxValidator
- API-FREEFree
- API-FREE+Free
- BULK-TRIALFree
- BULK-1$19.95, paid once
- BULK-5$39.95, paid once
- BULK-10$59.95, paid once
- BULK-50$149.95, paid once
- BULK-100$199.95, paid once
- BULK-500$399.95, paid once
- BULK-1000$699.95, paid once
In their own words
Abstract Email Validation API
Abstract Email Validation API checks whether submitted email addresses are correctly formed and can receive mail. One call checks address format, domain MX records, live SMTP without sending a message, and disposable or catch-all addresses. Responses arrive as structured JSON with deliverability, a quality score, SMTP status, and MX validation. The API supports signup form cleanup, B2B lead verification, and efforts to reduce bounce rates without tying a developer to one email provider. The product page says real-time validation responses arrive in under 300ms, and the API also supports bulk checks. CSV upload is included with listed paid plans. The Free plan includes 100 requests at three requests per second. Starter is $17 a month, billed annually, with 60,000 requests per year, three requests per second, domain whitelisting, and bulk CSV upload. The listed integrations include HubSpot, AWS, Salesforce, Zapier, Snowflake, Shopify, Make, Mailchimp, and Azure. The product page lists a 99.99% uptime SLA and describes privacy protections and compliance resources.
MailboxValidator
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.