Email verification for people who cannot afford a bounce.

Upload your list, see exactly what it will cost before anything runs, and get back the addresses that would have bounced — so the sender reputation you spent months building survives the next send.

  • You see the price before you spend it — we count your rows, remove duplicates, and quote the exact credits. Nothing runs until you press start.
  • Unknown results cost you nothing — when a server won't give a straight answer, you don't pay for it.
  • Catch-all domains named, never guessed — segment them instead of gambling the whole send.

100 free credits · No card required · Your file is deleted after 30 days, or immediately if you say so

100free credits to start
512 MBper upload
0charged for unknowns
Try it — verify one address live
Elapsed

The real verifier — 3 free checks, then create an account for 100 credits.

1 credit = 1 address verified 0 credits for duplicates, blanks and unknowns Results export to
CSVXLSXSuppression list JSON summaryREST APIWebhooks
Three steps

Upload your file. We verify. Download clean results.

Each panel below is the real interface, not an illustration.

1

Upload your file

CSV, XLS or XLSX. We detect the email column and show you what we found before anything is charged.

fileq3-outreach.csv
rows detected48,210
email columnC · work_email
duplicates1,904 removed — free
you will be charged46,306
2

We verify

Rows are checked in parallel and progress updates live. Close the tab — the run continues without you.

Verifying62%
29,910 / 48,210 rows2–4 min left
3

Download clean results

Full results, deliverable-only, or a suppression list of everything to remove — plus a JSON summary of exactly what was charged.

✓ deliverable38,911
✕ undeliverable5,102
△ risky2,190
? unknown703 — not charged
Result taxonomy

Every address comes back as one of seven results.

One vocabulary, normalised so it means the same thing on every file you ever run — whoever we checked it with.

Deliverable

DELIVERABLE

The mailbox exists and the server accepts mail for it.

Send.

Undeliverable

UNDELIVERABLE

The mailbox does not exist, or the domain cannot receive mail at all.

Remove.

Risky — catch-all

RISKY_CATCH_ALL

The domain accepts mail for every address, so the individual mailbox cannot be confirmed.

Send with caution, or segment.

Risky — role address

RISKY_ROLE

A shared inbox: info@, support@, sales@, billing@.

Exclude from cold sends.

Risky — disposable

RISKY_DISPOSABLE

A temporary or burner domain, created to expire.

Remove.

Risky — spam trap indicators

RISKY_SPAM_TRAP

Signals consistent with a recycled or pristine spam trap.

Do not send.

Unknown

UNKNOWN

The receiving server would not give a definitive answer, even after retries.

Not charged.

Unknown results cost you nothing.

When a receiving server won't give a definitive answer — greylisting, throttling, an outage — you are charged zero. The work ran at our expense, but you didn't get an answer you can act on, so you don't pay for it. It's itemised on your ledger, per file, every time.

Returned alongside every verdict

free_providerGmail, Outlook, Yahoo and similar, flagged.
mx_providerWho actually receives mail for the domain.
did_you_meanTypo correction — gmial.com → gmail.com.
confidence0–100 per address, so you can set your own cutoff.
Read the full accuracy reference →
Privacy and data handling

Your list is yours. We hold it, we verify it, we delete it.

You are handing us a customer list. Here is exactly what happens to it — and what never happens to it.

Encrypted in transit and at rest

TLS on the way in, encrypted storage on disk, and provider credentials sealed with a separate key.

Deleted on a schedule

Uploads and results are destroyed after 30 days. Delete now removes both immediately.

Never sold, shared or rented

Your addresses are not used to build a suppression database, a known-good list, or any other dataset.

Isolated per workspace

Isolation is enforced by the database itself, not just by application code. Results are never pooled across customers.

GDPR and CCPA requests

Access, export and erasure answered within 30 days. A DPA is available before you upload anything.

Read our data handling policy security@events.zylentix.com
Pricing

Buy credits once. Use them whenever.

1 credit = 1 address verified. Duplicates, blanks and unknown results are not charged. Nothing expires, ever.

Starter
USD 20
5000 credits
0.00400 each
✓ Credits never expire
Unknown results and duplicates are not charged.
Buy 5000
Growth
USD 150
50000 credits
0.00300 each
✓ Credits never expire
Unknown results and duplicates are not charged.
Buy 50000
Volume
USD 2000
1000000 credits
0.00200 each
✓ Credits never expire
Unknown results and duplicates are not charged.
Buy 1000000

What will my list cost?

pack
per address
Cost

Leftover credits stay in your account. There is no monthly plan to cancel, and duplicates and unknown results are not charged.

Comparison

Zylentix Verify against the typical verification tool

What you're buying Zylentix Verify Typical tool
Credit expiry Never expire Expire in 12 months, or a monthly plan
Unknown results Not charged at all Billed as a full credit
Duplicate rows Removed free at pre-flight Charged as separate addresses
Blank / malformed rows Not charged Often billed anyway
Cost shown before you spend Exact credit quote, then you confirm Charged on upload
API on the free tier Yes, every endpoint Paid plans only
Minimum purchase None — start with free credits $50–$100 minimum

"Typical tool" describes patterns common across the category, not any single named product.

Questions

The things people ask before they upload.

Still unsure? Send us a message — we answer within one working day.

What do you actually charge for?+

One credit per unique address that comes back with a usable result. Duplicates inside your file are removed before verification and never charged. Blank and malformed rows are not charged. Unknown results — where a server refuses to answer — are not charged either. You see the exact number before you press Start, and the unused part of the hold is returned the moment the file finishes.

What is a catch-all domain, and why can't you verify it?+

A catch-all domain is configured to accept mail for every possible address, so it answers yes to a real mailbox and yes to a made-up one alike. No verification service can tell them apart from outside. Anyone claiming to confirm individual mailboxes on a catch-all domain is guessing and charging you for it. We mark it risky, name the domain, and let you decide.

How accurate is this?+

We don't publish a headline accuracy percentage, because the number is meaningless without saying what happens to catch-alls. What we will tell you is the method: every address gets a 0–100 confidence score alongside its result, so you can set a stricter cutoff than ours, and anything we cannot answer confidently comes back as unknown and costs you nothing.

Do credits expire?+

No. Buy them today, use some this month and the rest next year. There is no monthly plan and no expiry date on any pack.

How long do you keep my list?+

Uploads and results are deleted automatically at the end of your workspace's retention window. There is also a Delete now control on every list that destroys the file and the results immediately. What survives is the summary line on your ledger — counts, credits and timestamps, with no addresses in it.

Is my list used for anything else?+

No. Your addresses are not sold, shared, rented, or used to build a suppression database, a known-good list, or a training set. Results are cached inside your own workspace so a repeat check is instant, and that cache is never read by another workspace. You can turn it off in Settings, which also deletes what is already stored.

Can I verify addresses at signup, through the API?+

Yes. A single POST returns a verdict synchronously, and it works on the free tier, so you can block bad addresses on your signup form before they ever reach your database.

What happens if I cancel a list halfway through?+

You are charged only for the rows already verified. Chunks still in flight are allowed to finish so their results are not wasted, and the rest of the hold goes straight back to your balance.

What file types and sizes can I upload?+

CSV, XLS and XLSX. We detect the email column, show you the row count, the duplicate count and the exact credit cost, and wait for you to confirm before anything runs.

Clean your list before your next send.

100 free credits, no card. You see the exact cost of any list before a single row is verified.

Start with 100 free credits
Free credits100
Card requiredno
Charged for unknownsno
Charged for duplicatesno
File retention30 days