Email Testing & Verification
APIs that validate email addresses, and SMTP sandboxes for testing email.
JSON: /api/v1/directory.json (filter on category=email-verification) · Agents can search it with the Swarmnest MCP Server
Email Testing & Verification
Mailpit
Local SMTP testing server with API.
FreeNo authMailHog
Email testing tool for developers.
FreeNo authOpen SourceMailtrap
Email sandbox and sending platform.
Free tierAPI keyHunter
Find and verify professional email addresses.
Free tierAPI keyZeroBounce
Email validation API.
Free tierAPI keyNeverBounce
Email verification service.
PaidAPI keyKickbox
Email verification API.
Free tierAPI keyEmailable
Email verification API.
Free tierAPI keyEthereal Email
Fake SMTP service by Nodemailer for catching test emails.
FreeNo authMailCatcher
Runs a local SMTP server and web UI to view sent mail.
FreeNo authPapercut SMTP
Desktop SMTP receiver for testing outgoing mail on Windows.
FreeNo authOpen SourceWindowssmtp4dev
Cross-platform dummy SMTP server.
FreeNo authOpen SourceMailSlurp
Programmatic disposable inboxes for tests with an API.
Free tierAPI keyMailosaur
Email and SMS testing API for QA.
PaidAPI keyMailinator
Public and private disposable inboxes with API.
Free tierAPI keyTestmail.app
Email testing with GraphQL and JSON APIs.
Free tierAPI keyLitmus
Email preview and rendering tests across clients.
PaidAPI keyEmail on Acid
Email client previews and spam testing API.
PaidAPI keyInbucket
Disposable email service for testing with REST API.
FreeNo authMailtrap Email Testing API
Sandbox inbox API to verify email in CI.
Free tierAPI keyMailDev
Node-based SMTP server and web interface for dev email.
FreeNo authHunter Email Verifier
Verify deliverability.
Free tierAPI keyAbstract Email Validation
Email validation API.
Free tierAPI keyMailboxValidator
Email validation API.
Free tierAPI keyVerifalia
Email verification.
Free tierAPI keyBouncer
Email verification.
PaidAPI keyMailcheck.ai
Disposable email check API.
FreeNo authDisposable Email Domains (GitHub)
Community blocklist of disposable domains.
FreeNo authOpen SourceReacher
Open-source email verification.
Free tierAPI keyOpen SourceClearout
Email verification.
Free tierAPI keyDeBounce
Email validation.
Free tierAPI keyTwilio SendGrid Validation
Email validation.
PaidAPI keyMailboxlayer
Email validation API.
Free tierAPI key