Letter Opener

Letter Opener: Preview Mail in Default Browser

A Rails plugin that intercepts Action Mailer messages, displaying mail body, headers, attachments, and more, for testing applications without sending emails during development.

What is Letter Opener?

Letter Opener is a Rails plugin that intercepts and displays email previews in the browser instead of sending them. It works by intercepting all emails sent through Action Mailer and rendering them in the browser, providing a convenient way to view the messages during development without actually sending anything.

Some key features and benefits of Letter Opener include:

• Preview email messages in the browser without needing to open a mail client
• No need to configure an SMTP server just for development/testing purposes
• Inspect headers, text content, HTML content, attachments for each message
• Works out of the box, no configuration needed other than adding the gem to your Gemfile
• See inline previews for attachments and images
• Supports mail clients that use ActionMailer 3.0 or later
• Open source and supported by an active community

By using Letter Opener, Rails developers can build and test emails for their applications without sending anything externally. It's perfect for previewing messages during development and debugging issues with content, formatting, attachments and more. And it requires no SMTP setup just to test emails.

Letter Opener Features

Official Links