mail.tm vs MailCheck.ai

mail.tm issues disposable inboxes on shared domains and exposes a Hydra/JSON-LD REST API to create accounts, fetch a bearer token, and read incoming messages, all without any signup fee. It's the fully free, actively maintained sibling of mail.gw.

MailCheck.ai has rebranded to UserCheck, but its original keyless lookup endpoint keeps working unchanged: pass an address and get back disposable, free-provider, MX, and domain-age signals in one JSON response, aimed at blocking throwaway signups. The rebranded product adds a free-to-start paid tier for higher-volume, authenticated use.