

Disposable inboxes for end-to-end signup tests, with long-polling and HMAC-signed webhooks.
Mailfornet API is a free Email API that requires apiKey authentication, is served over HTTPS and supports CORS, so it can be called from the browser.
A REST API that creates disposable inboxes and reads the mail that arrives. Built for signup and password-reset tests in CI. Free tier, then $0.01 per inbox.
Details from mailfornet.com.

Unified API suite · now live
Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Verify email deliverability with a strict yes/no, disposable and catch-all detection
Check a domain's SPF, DKIM, DMARC and MX records and get what to fix, with the values to publish
Email API and SMTP for sending transactional and bulk emails, with email testing sandbox for safe development
The Mailfornet API is provided by Mailfornet (mailfornet.com). A REST API that creates disposable inboxes and reads the mail that arrives. Built for signup and password-reset tests in CI. Free tier, then $0.01 per inbox.
Yes. The Mailfornet API is listed in the Email category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The Mailfornet API uses apiKey authentication, so you need to register for credentials before making requests.
Yes. The Mailfornet API supports CORS, so front-end JavaScript can call it directly.
Yes. The Mailfornet API is served over HTTPS, so it's safe to use in production.