
Mailinator
Disposable email testing inboxes with public and private domains
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Lightweight email testing tool with web UI and API
MailHog captures outgoing SMTP emails during development, letting you inspect messages in a web interface or via JSON API without sending to real recipients.
MailHog is a Go-based email testing tool designed to simplify SMTP testing during application development. It acts as a local SMTP server that captures all outgoing emails, preventing accidental sends to real recipients while providing full visibility into message content and structure.
Developers configure their applications to route SMTP traffic through MailHog's server (default port 1025). All captured messages appear instantly in a clean web interface (port 8025) with support for plain text, HTML, and raw source views. The tool includes a JSON API for programmatic access, enabling automated testing workflows. Messages can optionally be released to real SMTP servers when ready for delivery.
Built with Go, MailHog runs as a single binary with no installation dependencies across Windows, macOS, Linux, and FreeBSD. It supports modern SMTP standards including RFC5321, authentication (RFC4954), pipelining (RFC2920), and multipart MIME. Storage options include in-memory (default), MongoDB, or file-based persistence. The included Chaos Monkey feature helps test application resilience by simulating mail server failures.
MailHog suits development teams needing reliable local email testing, CI/CD pipelines requiring email verification, and anyone building applications with transactional email workflows.
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PHP Application Testing
Configure php.ini to route sendmail through MailHog, inspect registration and password reset emails locally without external SMTP
CI/CD Email Verification
Use JSON API in automated tests to verify email content, headers, and attachments after triggering application workflows
Microservices Development
Run MailHog in Docker alongside service containers to capture all SMTP traffic in isolated development environments
QA Failure Testing
Enable Chaos Monkey to simulate SMTP server failures and verify application retry logic and error handling
No. MailHog is a single Go binary that runs without installation on Windows, macOS, Linux, and FreeBSD. Download and execute to start capturing emails immediately.
Point your SMTP settings to localhost:1025 (default). For PHP, update php.ini with sendmail_path pointing to mhsendmail or use sendmail -S mail:1025.
By default, messages are stored in-memory and lost on restart. Configure MongoDB or file-based storage for persistence across sessions.
Yes. MailHog allows you to selectively release captured messages to real SMTP servers directly from the web interface or API.
SMTP server listens on port 1025 and the web UI/API runs on port 8025 by default. Both are configurable via command-line options.
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