SMTP vs API
SMTP and Email APIs are the two primary methods for sending email from applications. SMTP is the universal email transfer protocol that has existed since the 1980s. Email APIs are modern HTTP-based interfaces that offer better performance, error handling, and developer experience. Most email providers support both methods.
Comparison
SMTP is best for: legacy applications, CMS platforms (WordPress, Drupal), quick setup, and environments where you need universal compatibility. Configuration is simple: host, port, username, password.
Email API is best for: modern applications, high-volume sending, detailed delivery tracking, and when you need structured error responses. Requires code changes but offers better performance and features.
For new projects, prefer the Email API. For existing SMTP-based applications, SMTP relay is the path of least resistance.
Related Terms
Email API
A programmatic interface for sending, receiving, and managing emails from your application code.
SMTP Relay
A third-party SMTP server that routes your outgoing emails through trusted IP infrastructure.
Transactional Email
Automated emails triggered by user actions like password resets and order confirmations.
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