Normalize
Interpret syntax, Unicode and domain representation without silently rewriting the user’s intent.
INPUT AUTHORITYEvidence first.
Policy second.
Clean separates what can be observed from what should be concluded. That boundary is the foundation of every single-address result, bulk decision, API response and receipt.
01ObserveSyntax, routing and risk signals.
02InterpretPreserve uncertainty instead of guessing.
03DecideApply policy and seal the result.
SIX-STAGE EVIDENCE CHAIN
A decision you can reconstruct.
Each stage has a narrow job. Clean does not collapse every signal into one unexplained score.
Resolve
Observe domain routing, including MX, null MX and implicit MX conditions where applicable.
ROUTING EVIDENCEClassify
Surface role, disposable and typo risk as evidence—not as an automatic moral judgment about the address.
RISK EVIDENCEProbe
Authenticated workflows may add bounded mailbox-level SMTP evidence without sending a message.
PROVIDER EVIDENCEApply policy
Convert the available evidence into safe, review, suppress or unresolved under a declared policy.
DECISION AUTHORITYSeal
Preserve the evidence, policy output, confidence and immutable receipt so the decision remains inspectable later.
PROVENANCETHE BOUNDARY
What Clean knows is as important as what it refuses to claim.
Evidence about an address and its routing environment.
A technically usable address does not establish permission to contact a person.
Provider acceptance and inbox placement depend on systems beyond email verification.
Temporary or incomplete evidence can remain unresolved instead of being mislabeled invalid.
DECISION VOCABULARY
Four states. Each one says something different.
Evidence supports use under the selected policy.
Usable evidence exists, but risk or ambiguity deserves human or workflow review.
Evidence supports excluding the address under the selected policy.
Clean does not have enough trustworthy evidence to force a stronger conclusion.
Evaluate Clean by the evidence chain, not a magic number.
Open the buyer guide for the questions worth asking any verification platform.