smtp4dev - the fake SMTP email server for development and testing.
A dummy SMTP server for Windows, Linux, Mac OS-X (and maybe elsewhere where .NET Core is available). Lets you test your application without spamming your real customers.
smtp4dev support many advanced features:
- OpenAPI/Swagger API
- IMAP access to retrieve and delete messages
- SMTP session logging
- UTF8 support
- Viewport size switcher to simulate mobile etc
- Multipart MIME inspector
- HTML compatibility report and HTML validation
- TLS/SSL with implicit and STARTTLS modes and auto self-signed cert generation
- Authentication
- Multiple mailboxes along with rules to control what message goes where
- Reply, compose and relay messages including rules to auto relay
- Scripting expressions including error simulation
If you're looking for the older v2 Windows only GUI version. Grab it here.
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If you find smtp4dev useful, please consider supporting further development by making a donation .
Configuring your programs to send mails to smtp4dev