MailSift helps developers stop invalid, disposable, relay, typo, role-based, and risky emails before they enter a product or campaign. One API response combines 15+ checks with a 0–100 trust score in under 100 ms. Verify a single address, process CSV lists, or integrate through the API. Start with 500 free checks; paid credits never expire.

Hey Product Hunt 👋 MailSift is built around a simple idea: developers should be able to decide whether to trust an email address without stitching together DNS lookups, disposable-domain lists, and brittle rules. One API call checks syntax, MX records, disposable and relay providers, role addresses, domain age, SPF/DMARC, typos, catch-all behavior, and more. The result includes structured signals plus a 0–100 trust score, typically in under 100 ms. You can verify single addresses, clean CSV lists in bulk, or integrate directly into signup and lead workflows. Start with 500 free checks, and purchased credits never expire. I’d especially love feedback on the API response, trust scoring, and which integration you’d like us to build next. Thanks for checking out MailSift!

The trust score idea is really clever, and the speed is impressive. One thing I'd love to see is a webhook option so my server gets pinged automatically when bulk CSV jobs finish, instead of me polling for status. Would save a lot of time on larger list cleanups.

It would be super useful if the API response could flag whether an email belongs to a free provider like Gmail or Yahoo separately from the risk score, since that distinction matters a lot for B2B vs B2C campaigns and currently requires a separate lookup.

MailSift

Email verification for developers, in one fast API call

Email verification for developers, in one fast API call