Understanding results

Every verification returns a status, a more specific sub-status, a quality score, and a set of flags. This page explains each so you know what’s safe to send.

Statuses

Status	Meaning	Recommended action
`deliverable`	The mailbox exists and can receive mail.	Send.
`undeliverable`	The mailbox or domain cannot receive mail.	Remove / suppress.
`risky`	Deliverable but elevated risk (e.g. accept-all, role, full mailbox).	Send with caution or segment.
`unknown`	The mail server didn’t return a definitive answer.	Retry later; don’t bulk-send.

Sub-statuses

Sub-status	Under	What it means
`invalid_syntax`	undeliverable	Not a valid email format.
`invalid_domain`	undeliverable	Domain doesn’t exist or has no website/DNS.
`no_mx_record`	undeliverable	Domain can’t receive mail (no MX).
`mailbox_not_found`	undeliverable	The specific mailbox doesn’t exist.
`mailbox_full`	risky	Mailbox exists but is over quota.
`accept_all`	risky	Domain accepts all addresses; existence unconfirmed.
`role_based`	risky	Shared/role address (e.g. `info@`, `support@`).
`disposable`	risky	Temporary/throwaway address provider.
`timeout`	unknown	Mail server too slow to respond.
`no_connect`	unknown	Couldn’t connect to the mail server.

Quality score

A 0–100 score summarizing confidence and risk. Higher is safer. Use it to set your own threshold — for example, send to everything ≥ 80, review 50–79, and drop below 50. Tune the cutoff to your tolerance for bounces vs. reach.

Flags

Independent signals returned alongside the status:

Disposable — throwaway provider.
Role-based — not a personal mailbox.
Free — free consumer provider (e.g. Gmail, Outlook).
Accept-all — domain accepts everything.

Acting on results

Protect deliverability: never send to undeliverable.
Segment risk: treat risky separately — warm up, or exclude from cold sends.
Re-check unknown: these are often transient; retry before discarding.