Bulk CSV verification
Upload lists of 500,000+ rows — large files stream in the background while you watch live progress. No row limits per file, no babysitting.

Past a 2% bounce rate, providers start filtering you. We check every address and tell you which ones are safe to send.
2%
bounce rate is where mailbox providers start throttling
~30%
of a typical list goes stale in a year
What you pay
10 free
credits the moment you sign up — no card, no trial clock
1 credit
per verified address. Credits never expire, duplicates are free
Try it now
3 free checks, straight from this page. No signup, no card — see the verdict quality for yourself.
Syntax
RFC compliance check
Domain
DNS & MX records
Mailbox
SMTP handshake
Signals
Disposable & role checks
How it works
No setup calls, no integrations required. Most lists finish verifying in minutes.
Drop a CSV or paste from a spreadsheet. Duplicates are removed at import, so you never pay twice.
Syntax, domain and mailbox-level checks. Nothing is ever sent to your contacts.
Valid, invalid, risky, catch-all or unknown — each with the reason attached.
Filter to valid-only in one click, then load the clean file into your sending tool.
Verdicts
Valid
Valid
The mailbox exists and accepts mail.
Keep it — send with confidence.
Invalid
Bad syntax, no mailbox, or no mail server behind the domain.
Remove it before your next send.
Risky
Disposable, role-based (info@, sales@), or low-quality address.
Send with caution, or segment it out of important campaigns.
Catch-all
The domain accepts every address, so the specific mailbox can't be confirmed.
Segment separately and watch engagement before trusting it.
Unknown
The mail server didn't give a clear answer — timeouts or greylisting.
Retry later, or exclude it from sends that matter.
Features
Built around one job: telling you which addresses deserve your sending budget.
Upload lists of 500,000+ rows — large files stream in the background while you watch live progress. No row limits per file, no babysitting.
One credit checks one address, and credits never expire. No subscription, no monthly minimum, no meter running while you sleep.
Paste one address, get a verdict in seconds. Handy for checking a signup before it hits your CRM or a reply-to before you commit.
We flag domains that accept everything and mailboxes built to expire in ten minutes. Both quietly wreck engagement stats if you let them through.
info@, sales@, and support@ addresses reach shared inboxes, not people. We mark them so you can keep them out of personal-touch campaigns.
Export the whole result set or just the valid addresses — one click either way. Every row carries its verdict, sub-status, and score.
Who it's for

Your newsletter list has been collecting addresses for three years, and last month's bounce rate crept past 3%.

A new client hands you a 'great list' of 80,000 contacts with no export date and no opt-in records.

Checkout typos and throwaway addresses pile up all year, and your abandoned-cart flow quietly bounces against a slice of them.

Signups arrive with typos and disposable addresses, and the onboarding sequence never lands for a chunk of your trials.

Your SDRs pull prospect emails from a dozen sources, and every bounced sequence step nudges your domain toward the spam folder.
Pricing
Prepaid credit packs — one credit verifies one address. No subscription, no renewal date, no surprise invoice.
5,000 credits
$20
$0.004 / email
For a first clean-up, or a list you send to occasionally.
Get startedWhat you get:
25,000 credits
$80
$0.0032 / email
For a list you send to every month and cannot afford to bounce.
Get startedEverything in Starter, plus:
100,000 credits
$250
$0.0025 / email
For teams verifying continuously across several lists.
Get startedEverything in Growth, plus:
500,000 credits
$900
$0.0018 / email
For agencies and senders working at half a million and up.
Get startedEverything in Scale, plus:
Every new account starts with 10 free credits. Volume beyond 500k? support@validemailer.com
FAQ
Straight answers — including the ones other verification tools dodge.
Above roughly 2%, start watching closely — mailbox providers notice. Above 5%, they actively throttle or block you, and recovering a damaged domain takes weeks. Cleaning before you send is far cheaper than repairing after.
A catch-all domain accepts mail for any address, real or not, so the specific mailbox can't be confirmed from the outside. No service can fully verify a catch-all — anyone who claims otherwise is guessing. We label them plainly so you can segment and watch engagement instead of gambling a whole send on them.
No. Buy a pack today, use it whenever your next list shows up. There's no subscription and no clock running.
For addresses that come back valid or invalid, accuracy runs in the high 90s. But some mail servers simply refuse to answer clearly — those come back as unknown, and we tell you rather than folding them into a prettier number. An honest unknown beats a confident guess.
Never. Verification happens at the infrastructure level — syntax checks, DNS and MX lookups, and mailbox-level conversations with the receiving server. Your contacts never see anything, and nothing lands in their inbox.
Your lists are yours. We store them and their results only so you can review and export; delete a list — or your account — anytime and the data goes with it. We never sell or share your addresses. Details in the privacy policy.
Yes — one click. Filter the results to any verdict and export exactly that slice, or grab the full file with every verdict, sub-status, and score attached.
We dedupe at import, before verification starts, and the duplicates cost you nothing. You pay one credit per unique address — never twice for the same one.
Payments run through Stripe and accept major cards. If you change your mind, unused credits from a pack purchase are refundable within 14 days — see the refund policy for the details.
Social proof
6.2% → 0.9%
bounce rate, first send
We cleaned a 40k list before our product launch, and our open rate finally matched what the copy deserved.
Day one
every client onboarding
A verification pass surfaces the real state of their list immediately — it has saved us at least two awkward deliverability conversations.
Under 1%
outbound bounce rate
Our SDR team verifies every prospect batch before it enters a sequence, and our domain stopped tripping spam filters.
Upload a list, get verdicts in minutes, and send to the addresses that are actually there.
No credit card required. Credits never expire.