What each result means, how confident you can be, and what to do with it.
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. |
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.
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.