Guerrilla Mail vs mail.gw

Guerrilla Mail issues disposable, auto-expiring inboxes and lets a client poll or fetch their incoming messages through a simple JSON-over-AJAX endpoint, no signup or key required. It's a fully free anti-spam utility with no paid tier.

mail.gw is a temporary/disposable email API that issues throwaway inboxes for testing signups and email-verification flows. Its Hydra/JSON-LD REST API is rooted at api.mail.gw, exposing /domains (available disposable-email domains) and /messages collections, with no API key required for the base entrypoint.