uptime · 99.998% · last 90 days

One upload.
A clean list.
Every time.

ZenVerifier sorts the deliverable from the dead before you hit send. Drop a CSV, get a clean list back in eleven minutes — no developer, no ‘configure your DNS,’ no learning curve.

Start with 50 free →See how it works
No credit card·SOC 2 Type II·GDPR · EU residency
~/lists · zenverifier · 96×24
→ verify spring_promo.csv
reading 28,419 rows · column ‘email’ detected
resolving MX · 412 unique domains
pinging mailboxes · 8 workers
✓ 24,108 deliverable (84.8%)
~ 2,184 catch-all (7.7%)
~ 803 role-based (2.8%)
✕ 1,324 invalid (4.7%)
→ wrote clean.csv · 11m 14s
→ est. saved on next campaign:
$1,420 in sender-reputation cost
→
12,400 marketing teams verify with ZenVerifierFrom solo senders to 100m+ subscriber lists
2.4B emails verified0.6% avg post-clean bounce11 min median 50k-row list99.9% deliverable-detection accuracy30+ countries
The math nobody runs

Sending to a dirty list costs more than cleaning it.

Every uncleaned campaign quietly drains your sender reputation, your seat budget, and your conversion rate. Here’s what most teams don’t see until it’s too late.

✕ Without ZenVerifier
50k-list / month
  • –
    Sender reputation crashes after 2% bouncesGmail starts routing your campaigns to Promotions or Spam — and recovery takes weeks.Source: Gmail Postmaster Tools, 2025
  • –
    $184/mo wasted on Mailchimp seats for invalidsMost ESPs charge per contact — clean or not. A 12% invalid rate is $22/mo of pure waste per 5k contacts.Based on Mailchimp Standard tier pricing
  • –
    6+ weeks to recover from a blacklistingOnce you’re on Spamhaus or Barracuda, you’re not getting off quickly. Removal is manual and slow.Spamhaus removal docs · 2024
✓ With ZenVerifier
same list, cleaned
  • +
    0.6% avg post-clean bounce rateStay comfortably below the 2% threshold ESPs and inbox providers care about.Avg across 12,400 ZenVerifier customers
  • +
    Pay only for valid contactsDrop the 12% that would’ve cost you anyway — and let your ESP charge you for people who actually open.Customer-reported avg savings: $156/mo
  • +
    +18% open rate, on averageSender rep up, dirty contacts gone, more emails landing in primary. Compounds with every send.Pre/post study, Q1 2026, n=842 customers
How it works

Drop. Grade. Ship.

Three steps, eleven minutes, zero training. The whole thing fits between your morning coffee and your standup.

01Drop your list
CSV in. Or paste it. Or sync.

Upload any CSV up to 1M rows, paste a column from Google Sheets, or sync from Mailchimp / Klaviyo / HubSpot in one click.

spring_promo.csv
28,419 rows · 412 KB
↑ uploading · 84%
02Eight signals run
Every address through eight checks.

Syntax. MX. SMTP. Catch-all. Disposable. Role. Typo. Graylisting. Each address gets a 0–100 score and a clear verdict.

✓ syntax · mx · smtp
~ catch-all · role
✕ disposable · typo
03Ship it back
Clean list, same place.

Download the cleaned CSV, or push it straight back to your ESP. Bad contacts removed, risky ones tagged, deliverable ones ready to send.

clean.csv · 24,911 rows
removed: 1,324 · review: 2,184
↓ download · ready
The 8-layer engine

Every address, eight ways.

Most verifiers stop at MX + SMTP. We don’t. Eight independent signals — any one can downgrade an address, none can upgrade it. That’s why our deliverable count is honest, not optimistic.

layer 01
syntaxsyntax
RFC 5321 / 5322 compliance — does the address even look like one?
missing @, malformed domains, encoding bugs
layer 02
mxmx
Does the domain have working MX records pointed at a real mail server?
expired domains, parking pages, broken DNS
layer 03
smtpsmtp
We open a connection to the inbox and ask 'do you exist?' without sending.
deactivated mailboxes, full quotas, frozen accounts
layer 04
catchcatch-all
Probe the domain for accept-all behavior and classify confidence accordingly.
false-positive deliverables that bounce silently
layer 05
disposabledisposable
Check against a daily-updated list of 14,000+ throwaway-email providers.
mailcat, mailinator, 10minutemail, YOPmail, etc.
layer 06
rolerole-based
Detect info@, support@, hr+jobs@ — addresses that route to a team, not a person.
low-engagement aliases that drag your open rate
layer 07
typotypo
Flag and suggest fixes for common domain mistakes (gnail.com, yaho.com).
human-error addresses that always bounce
layer 08
graylistinggraylisting
Detect anti-spam graylisting and retry with the right backoff. No false negatives.
addresses other verifiers wrongly mark invalid
Built for the marketer, not the engineer

No code. No setup. No ‘ask your dev.’

Open the dashboard. Drop your list. Get a clean one back. The whole thing looks like the tools you already use — because the people who built it spent ten years building those tools.

  1. 01
    Sign in with one click
    Google or email. Your team workspace appears in five seconds.
  2. 02
    Drag your CSV into the dashboard
    We auto-detect the email column, dedupe, and start verifying.
  3. 03
    Watch the verdicts come in live
    Sortable, filterable, exportable. Catch-all and risky addresses tagged so you can decide.
  4. 04
    Download or sync back
    Push clean contacts straight to Mailchimp, Klaviyo, HubSpot — or grab the CSV.
spring_promowinback_q2+ new
28,419 rows · 11m 14s · ✓ done
24,108
Deliverable
2,184
Catch-all
803
Role
1,324
Invalid
alex@duncan-textiles.comduncan-textiles.com● Deliverable98/100
ops@petalpath.iopetalpath.io● Catch-all62/100
marisol.b@quietkettle.coquietkettle.co● Deliverable96/100
noreply@mailcat.appmailcat.app● Disposable8/100
hr+jobs@plover.studioplover.studio● Role48/100
“

Our open rate jumped 31% the week we cleaned. We canceled the entire re-engagement campaign and just went and made better emails instead.

M
Mireille DevereauxLifecycle marketing · Petunia
+31%
Open rate, week 1
0.4%
Bounce rate, ongoing
412k
Subscribers cleaned
Pricing

Pay for what you actually verify.

Every plan includes every check. Pick a volume, change anytime. Credits refresh monthly — clean and simple.

Free Trial
Try before you commit.
Free/ 50 credits
  • 50 verifications / month
  • No credit card required
  • Full feature access
Get started
Starter
For small projects.
$37/ mo
  • 10,000 verifications / month
  • Every check (8-layer engine)
  • Single email + bulk CSV verify
  • Re-verify unknowns at no extra cost
  • Team workspace + invites
  • Priority email support
  • Refreshes monthly · no rollover
Choose plan
Popular
Growth
For growing businesses.
$49/ mo
  • 25,000 verifications / month
  • Every check (8-layer engine)
  • Single email + bulk CSV verify
  • Re-verify unknowns at no extra cost
  • Team workspace + invites
  • Priority email support
  • Refreshes monthly · no rollover
Choose plan
Professional
For high volume.
$77/ mo
  • 50,000 verifications / month
  • Every check (8-layer engine)
  • Single email + bulk CSV verify
  • Re-verify unknowns at no extra cost
  • Team workspace + invites
  • Priority email support
  • Refreshes monthly · no rollover
Choose plan
Enterprise
For large scale.
$129/ mo
  • 100,000 verifications / month
  • Every check (8-layer engine)
  • Single email + bulk CSV verify
  • Re-verify unknowns at no extra cost
  • Team workspace + invites
  • Priority email support
  • Refreshes monthly · no rollover
Choose plan
Security & compliance

Your list is yours.

We hold your contacts long enough to verify them — and not a day longer. Audited, encrypted, regional, deletable.

SOC 2 Type II
Audited annually. Report available on request, under NDA. Subprocessor list public.
GDPR & EU residency
Data processed in Frankfurt by default. DPA signable in two clicks from billing.
30-day max retention
We don't keep your list. Auto-delete after 30 days, on-demand delete anytime.
Never trained on
Your contacts are never used for training, marketing, or anything other than verifying.
Frequently asked

Honest answers to the questions you’d actually ask.

No. Your list lives in your workspace, processed only to verify, deleted after 30 days (or sooner on demand). We don't train models on it. We don't share it with anyone, including subprocessors who don't need access. This is in our DPA, not just on this page.

Stop sending
into the void.

Verify 50 emails free →Talk to us
No credit card · No ‘book a call’ wall · Cancel anytime
ZenVerifier — clean lists, calm sends