Every address you validate comes back with one verdict. Here is what each one actually means — and the honest part: what it can and cannot promise.
| Verdict | Meaning | What to do |
|---|---|---|
| Deliverable | The mailbox was confirmed at the receiving server. | Safe to send. |
| Undeliverable | The server rejected the mailbox, or the domain cannot receive mail at all. | Remove it — sending will bounce. |
| Risky | The mailbox likely exists but showed a caution signal — full inbox, slow greylisting, or similar. | Send carefully, in smaller batches. Details. |
| Accept-all | The domain accepts every address, so no one can confirm an individual mailbox there. | Segment and warm up. Details. |
| Disposable | A temporary-inbox service. | Drop it — it will not convert. |
| Unknown | No definitive answer could be obtained in time. | Nothing — unknowns are not charged. |
The confidence score
Alongside the verdict you get a 0–100 score reflecting how strong the evidence was — a deliverable confirmed by a direct mailbox response scores higher than one inferred from patterns. Use it to set your own risk threshold when a simple verdict is not enough.
The reason field
Exports include the specific reason behind each verdict — smtp_verified, mailbox_full, no_mx_records, disposable_email and so on — so you can audit any decision instead of trusting a label.