Overview

See how an email or domain becomes an allow, review, or block decision.

SignupScore checks an email address or domain before you create an account. Each check returns one clear action: allow, review, or block.

How a check works

You sendSignupScore checksYou get
name@example.comThe address, domain, mail servers, and your protection rules.An action with the reasons behind it.
example.comThe domain, mail servers, and your protection rules.A domain-level action and reasons.

Email input gives SignupScore more to work with. For example, it can recognize shared addresses such as support@, tagged aliases such as name+trial@, and addresses that strongly resemble generated junk.

Example decisions

The same endpoint can return different actions for different signups:

InputExample resultA sensible next step
alex@company.comallowContinue account creation.
support@new-domain.testreviewRequire email verification or another check.
name@tempmail.comblockStop signup with a neutral message.

These are examples, not fixed rules for every account. Your protection settings can allow a trusted domain, block a domain that has caused abuse, or review newly registered domains.

What the response means

Use action for the signup decision. Use primary_reason and reasons when you need to understand or record why it happened. Keep request_id when you need to find the same decision in your dashboard.

SignupScore does not return an invented 0 to 100 fraud score. It returns the facts it found and the action produced by those facts and your rules.

Where to start

Start with the Quickstart. Then read Actions to choose what review should mean in your product and what to do if the API is temporarily unavailable.