VouchleyDisposable email database
Is mailsac.com a disposable email?
Quick answer
mailsac.com is operated by Mailsac, a disposable / temporary email service. Signups using this domain are almost always throwaway. Block at signup if your product depends on long-term email reachability.
About Mailsac
Mailsac is a developer-oriented disposable email platform: public throwaway inboxes plus a full REST API and webhooks for reading mail programmatically. Engineering teams legitimately use it to test their own signup flows in CI — which is exactly what makes it potent for automating signups on someone else's product.
What it’s typically used for
Email-flow testing by developers, and automated account creation when pointed at third-party products. Public inboxes also serve ordinary throwaway signups.
Should you block mailsac.com in your signup form?
Block on production signup forms. If your own team uses Mailsac for end-to-end tests, allowlist it in test environments specifically rather than letting it through everywhere.
How to detect mailsac.com in code
You don’t need to maintain a hand-rolled list. Vouchley returns a disposable flag (and the rest of the signup score) on every check:
curl -X POST https://api.vouchley.getrevlio.com/v1/verify \
-H "Authorization: Bearer vch_live_..." \
-H "Content-Type: application/json" \
-d '{
"email": "anyone@mailsac.com",
"ip_address": "203.0.113.10"
}'
# Response:
# {
# "score": 12,
# "recommendation": "block",
# "email": { "disposable": true, "valid": true },
# ...
# }Block disposable signups in one API call.
Vouchley keeps the disposable list current — including alias domains and new providers — so you never have to maintain it yourself.