Bulk email verification
Turn a list into decisions.
Upload what you already have and let it run. What comes back is rows you can act on, each one carrying the same status, recommendation and reason codes as a single check.
No message is ever sentExport filtered by outcome
| Outcome | Rows | Share |
|---|---|---|
| Deliverable | 104,852 | 83.6% |
| Risky | 9,112 | 7.3% |
| Undeliverable | 9,804 | 7.8% |
| Unknown | 1,652 | 1.3% |
Made-up figures, for the sake of the example. No two real lists break down alike.
How it works
Upload, verify, export.
01 · Upload
Bring the list you already have
A CSV with a column of addresses. Duplicates are collapsed before any work starts, so the same address is never checked twice in one run.
02 · Verify
Watch it work through
Rows settle as the evidence arrives. The ones needing a mailbox probe are queued and polled on a bounded interval, so a slow provider holds up its own row and nothing else.
03 · Review and export
Take only what you need
Filter by status, by recommendation, or by one specific reason code. Export that selection with the evidence columns attached and the rest of your file untouched.
What a finished run looks like
Rows you can filter and act on.
| Address | Status | Action | Reason codes |
|---|---|---|---|
| info@acme.example | Risky | challenge | ROLE_ACCOUNT |
| k.novak@catchall.example | Risky | challenge | ACCEPT_ALL_DOMAIN |
| test@mailinator.example | Risky | challenge | DISPOSABLE_DOMAIN |
| j.smith@gmial.example | Risky | challenge | LIKELY_DOMAIN_TYPO |
Example rows. .example domains are reserved by the standards bodies, so none of these is anybody’s real address.
Risky is one status covering several quite different causes, and the reason code tells you which one you have got. A shared inbox and a mistyped domain both deserve a second look. Just not the same one.
Capabilities
What actually happens to your file.
Before anything is checked
Syntax normalised, international domains handled, duplicates collapsed, and near-misses of well-known domains flagged for what they probably were.
The checks themselves
Does the domain exist, where does its mail go, will the server take this recipient — plus the catch-all, burner and shared-inbox signals around all three.
What comes back
Status, recommendation, reason codes, an evidence score, and how fresh the DNS and SMTP evidence behind each row is.
Scale
How long a big list takes depends on the list.
Throughput comes down to how many addresses need a mailbox probe and how the receiving providers are behaving that day. We publish measured figures once we have them, and not a moment before.
largest list tested
addresses per minute
maximum upload size
charging for duplicates and unknowns
Marked figures are waiting on approval. Freshness is reported per row: DNS evidence and SMTP evidence go stale at very different speeds, so each one gets its own timestamp.
Your list
Your file is a liability we are holding for you.
What we can tell you today
Nothing is delivered to any address on your list. We keep the results, so a repeat verification doesn’t go back and probe a mail server again. And the reply text those servers send us never reaches anything you can see: you get stable codes instead.
What Legal still has to confirm
Encryption at rest [STATEMENT], retention window [PERIOD], deletion on request [PROCESS], processing regions [REGIONS], and any certifications actually held.
Bulk questions
Before you upload.
Which file formats are supported?
CSV, with one column of addresses. Any other columns you bring are carried through to the export untouched, so what comes back still fits whatever you were doing with it. Size and column limits are published with the commercial terms.
How long does a list take?
That depends on the list more than on us. Addresses settled by syntax, DNS and routing finish almost at once. The ones needing a mailbox probe get queued, and the receiving providers set the pace — some greylist on purpose, which means coming back later rather than waiting longer now.
Are duplicates charged?
Duplicates are collapsed before any work starts, so the same address is never verified twice in one run. How that maps onto credits is part of the credit policy, which Commercial settles before launch.
What happens to unknown results?
They stay unknown. It means no safe answer was available, usually because a provider timed out, throttled us, or hides whether a mailbox exists. Coming back later can change that answer. Guessing can’t.
Can I export only deliverable addresses?
Yes. The export follows whatever filter you’ve applied — by status, by recommended action, or by a specific reason code — so you can pull exactly the rows one workflow should get and leave the rest behind.
How long is my uploaded file kept?
There is a retention window, and it is stated in the privacy policy. We’ve deliberately not printed a number here until Legal has confirmed it, because a retention period you can’t rely on is worse than none at all.
Start with one list.
Upload what you have, look at how it breaks down, and decide what to do about it.