Inbucket is an email testing application; it will accept messages for any email address and make them available to view via a web interface. If you’ve ever used, you already have a good idea of what Inbucket does. The benefit of Inbucket is that it is an application instead of a hosted service; you may run it on your own private network, or even your desktop.

Inbucket allows web developers, software engineers, and system administrators to quickly see the emailed output of their applications. No per-account setup is required! Mailboxes are created on the fly as mail is received for them, and no password is required to browse the content of the mailboxes.

Inbucket has built-in SMTP and POP3 servers which store incoming mail as flat files on disk – no external SMTP or database daemons required.

Inbucket was written in Google Go and is open source software released under the MIT License.

Mail features

  • Receive and store E/SMTP messages
  • Purge messages after a configurable amount of time
  • Enforce a cap on the number of messages per mailbox by deleting older messages
  • Optional load test mode; no messages are ever written to disk
  • Configurable load test domain; messages addressed to it are never written to disk
  • Access mail via embedded POP3 server


Web-interface features

  • List messages in a mailbox
  • Displays text content of a particular message
  • Displays source of a message (headers + body text)
  • Displays HTML version of a message (in a new window)
  • List MIME attachments with buttons to display or download
  • Delete a message
  • Monitor – a real-time display of received messages
  • RESTful: REST API Docs

Why Inbucket?

Need to test your web apps outbound emails with Mailinator but stuck behind a firewall? Want to keep the new application you are developing secret until it’s time to release it? Need to validate that emails go out as part of your integration test suite? Want to send a link to a coworker demonstrating an email without giving them your Gmail password? Need to load test your application without melting your corporate Exchange server? Want to use production data in your test environment without the risk of test messages leaking to an end user? Need to preview emails in multiple desktop email clients? Use Inbucket!

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