Mailgun

Transactional email API built for developers, enabling programmatic sending, receiving, parsing, and tracking of emails at scale. Integrates into applications via REST APIs and official SDKs for major languages, with support for webhooks, routing rules, and detailed analytics.

Trusted by over 150,000 businesses, including 8 of the 10 largest tech companies. Differentiates through developer-first design and reliability: built by developers for developers, with compliance and deliverability tooling. Combines sending infrastructure with validation, inbox preview, and optimization features in a single platform.

Key capabilities:

• REST API and official SDKs for PHP, Python, Go, and others
• Inbound email parsing and webhook routing
• Email validation API for list hygiene before sending
• Inbox preview and accessibility checks before campaign delivery
• Domain verification, DNS management, and bounce handling

Developers use it for transactional flows such as password resets, order confirmations, and notification digests. Teams building user-facing apps integrate the API directly into backend services, while marketing and operations teams rely on validation and preview tools to improve deliverability and compliance. Works with webhook endpoints for real-time event handling and supports custom routing for incoming mail.