Validate Your Email List Before Sending
Validate Your Email List Before Sending: upload a CSV or connect your CRM, and Cleanlist AI checks each row against 25+ providers in sequence. Every new workspace opens on Pro for 14 days with 250 credits, 3 seats.
Cleanlist AI validating email-list.csv. Each address is marked Verified, Likely valid, Risky, Invalid or Unknown. Of 10,000 rows, 8,612 Verified, 604 Likely valid, 431 Risky, 287 Invalid, 66 Unknown.
10,000+ users, from founders to full sales teams
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How does Cleanlist AI validate your email list before sending?
Cleanlist AI's list validation checks every address against five validation layers before you press send: syntax and formatting, DNS and MX records, SMTP mailbox existence, catch-all domain detection, and behavioral activity scoring. You get the list back sorted by deliverability risk: send to the safe addresses and hold back the risky ones.
Why this is hard to do by hand
An unvalidated list looks fine right up until the campaign goes out. Mailbox providers weigh opens, clicks and complaints alongside bounces when they decide where your mail lands. One campaign to a stale list can drag your sender score down hard, and Return Path's 2025 benchmark put the average recovery at 42 days of carefully throttled sending.
Sender reputation takes 42 days to recover after a bounce spike
42 daysaverage time to recover sender reputation after a bounce spike
Return Path's 2025 Sender Score Benchmark looked at 3,200 sending domains. Those that bounced above 5% on a single campaign took an average of 42 days to get back to their earlier sender score. Inbox placement dropped 18-35% in the meantime, so a real share of legitimate mail went to spam. Recovering means sending small, growing batches to your most engaged subscribers only, and earning back the mailbox providers' trust one batch at a time. Validating a 25,000-address list before the send costs 12,500 credits, at 0.5 per address.
Source: Return Path (now Validity) Sender Score Benchmark 2025
What a lookup costs
Each lookup walks 25+ providers in cost order, and you're charged once for what comes back: 1 credit for a verified work email, 10 for a phone number, 11 for both. Validation is 0.5 and AI qualification is 5. A lookup that finds nothing is free, and the whole team pays from one wallet.
- Verified work emails25 leads searched23 × 123
- Phone numbersVerified before anyone calls18 × 10180
- Qualification agentFit score with reasons25 × 5125
- 25+Providers queried in cost order on a single lookup
- 98%Verified work emails on our 500-lead benchmark
- 85%Phone numbers found on that same benchmark
- 0Credits for a lookup that finds nothing
How it works.
- 01
Upload the list you're about to send
Upload the exact send list as a CSV or Excel file, or paste it. Cleanlist AI keeps your segmentation columns, so the validated file goes back into your ESP with the audience structure intact.
- 02
Syntax and formatting pass
Cleanlist AI flags missing @ signs, double dots, invalid TLDs and non-ASCII characters first. Common typos (gmial.com, yaho.com, outlok.com) are corrected when the fix is unambiguous, so those contacts stay on the list.
- 03
Domain health check
Cleanlist AI checks each domain for active MX records, SPF, DKIM and DMARC setup, and blocklist status. Domains that can't receive mail or sit on a major blocklist get flagged, so you remove them before they hard-bounce.
- 04
Mailbox check
On domains with a live mail server, Cleanlist AI runs the SMTP handshake for each address. That confirms the mailbox itself exists and accepts mail.
- 05
Sort by deliverability
The list comes back in four tiers: Safe (verified mailbox, active domain), Acceptable (valid, on a catch-all domain), Risky (unreliable server, greylisted) and Suppress (invalid, trap or blocklisted domain). Send to Safe and Acceptable.
What you get.
98% verified work emails
That's on our 500-lead benchmark. Cleanlist AI checks each email and flags catch-all and disposable addresses before you send.
25+ data providers
Cleanlist AI asks them one at a time and stops at the first deliverable result. When one provider has nothing, the next one gets its turn.
No code required
Upload a CSV or connect your CRM. If your engineers want it, the API is there from the Pro plan.
14-day Pro trial
250 credits and 3 seats on Pro for 14 days. You don't need a card or a sales call to start.
Manual process vs Cleanlist AI.
| Feature | Manual | Cleanlist AI |
|---|---|---|
| Validation layers | One: send and see what bounces | Five: syntax, DNS, MX, SMTP, activity |
| Typo auto-correction | None, so typos become hard bounces | Common domain typos fixed automatically |
| Blocklist checking | Manual lookup on MXToolbox (one domain at a time) | Every domain checked against major blocklists in one pass |
| Validating 25K addresses | Not feasible by hand, so teams wait for bounce data | 12,500 credits, at 0.5 per address |
| Sender score protection | The damage lands before you see it | Risky addresses held back before the send |
How accurate is Cleanlist AI's data?
Cleanlist AI returned 98% verified work emails and 85% phone numbers on our 500-lead benchmark, pulling from 25+ data providers. Each lookup stops at the first deliverable result, meaning a verified or likely-valid email.
What do I get when I sign up?
A 14-day Pro trial: 250 credits, 3 seats, and every Pro feature. After it, the Free plan gives you 50 credits a month. A verified work email costs 1 credit, a phone number 10, and a miss nothing.
What data providers does Cleanlist AI use?
Cleanlist AI runs a waterfall across 25+ B2B data providers. For each record it asks one, moves to the next when that one has no match, and stops at the first deliverable result.
Can I connect my CRM?
Yes. HubSpot and Salesforce sync both ways on the Pro and Enterprise plans, and Salesloft and Lemlist take a one-way push. You can also upload a CSV, or use the REST API from Pro.
How long does it take to validate my data?
It depends on the size of the file and how far down the waterfall each row has to go. Cleanlist AI runs the whole CSV as one job, so you upload once and download or sync the results when it's done.
What is the difference between email validation and email verification?
Most people use the terms interchangeably. Strictly, validation checks that an address follows the rules (syntax, a real domain), and verification confirms the mailbox exists and accepts mail. Cleanlist AI runs both, syntax checks and SMTP verification, so you get the same result either way.
Should I validate my list every time I send a campaign?
Validate monthly if you mail the same list every week. Validate before every campaign if the list has new contacts from events, bought lists or webforms without double opt-in. At 0.5 credits per address, it costs far less than a hit to your sender reputation.
Can Cleanlist AI validate emails in languages other than English?
Yes. Validation runs on the protocol (DNS and SMTP), so the language of the domain doesn't matter. International domain names with non-Latin characters are supported.
Describe the job once. An agent runs it every week.
Clu turns one sentence into an agent. It searches 1B+ profiles, finds verified emails and phone numbers across 25+ providers, adds the people to your sequence and posts each run to Slack.
Weekly ICP outbound
Built by Clu from: “Every week, find 500 new people who match my ICP, get their emails and phones, and add them to Series B outbound.”
- Searched 1B+ profiles for new ICP matches500 foundPeople Search
- Ran the waterfall across 25+ providers487 emails · 412 phonesWaterfall
- Verified every email and phoneSMTP + catch-allVerification
- Added them to Series B outbound500 peopleSequences
- Posted the run to #pipelineSlackAgents
Friday 4:52 PM15 replies · 5 calls booked
Everything in the 14-day Pro trial
- Clu and agentsDescribe the job in one sentence. Clu builds the agent, runs it on a schedule or a CRM trigger and posts every run to Slack.
- People and Company SearchFind your buyers in 1B+ profiles from one sentence. Searching costs 0 credits.
- Waterfall enrichmentAsk 25+ providers in order and stop at the first verified email or phone number. 98% verified work emails and 85% phone numbers on a 500-lead benchmark.
- Email verificationRun SMTP and catch-all checks on every address before it reaches a sequence, at half a credit an email.
- ICP scoringScore every lead 0 to 100 against your ICP, with the reasons written down. The Research and Qualification skills do the digging.
- SequencesSend email from your reps' own inboxes, with call tasks. A reply stops the sequence. Sending costs 0 credits.
- CRM syncTwo-way sync with HubSpot, Salesforce and Pipedrive. Push finished lists to Outreach, Salesloft and Lemlist.
- Chrome extensionGet a verified email and phone number in one click on LinkedIn, Sales Navigator, Salesforce and HubSpot.
- MCP and APIRun the same search and waterfall from Claude or ChatGPT with 36 MCP tools, or from your own code with the REST API.
14 days of Pro, free: 250 credits, 3 seats, agents, Sequences and Clu in Slack. Then Free at 50 credits a month, or Starter at $49 and Pro at $89 a seat a month.
Hand the job to an agent.
Upload a CSV or connect HubSpot, Salesforce or Pipedrive, and run it on your own data today.
14 days of Pro, free.
Get 14 days of Pro, free.
250 credits and 3 seats. Sign up with your work email for 100 more.