Clean Your Mailing List for Better Deliverability
Clean Your Mailing List for Better Deliverability: 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 mailing-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 clean your mailing list for better deliverability?
Cleanlist AI cleans mailing lists by running every address through multi-layer verification: SMTP validation confirms the mailbox exists and is accepting mail, catch-all detection identifies domains that accept everything (making verification unreliable), disposable email detection catches temporary addresses, role-based detection flags shared inboxes, and engagement-risk scoring identifies addresses likely to generate spam complaints. You get the list back in three groups: safe to send now, risky (handle with care) and invalid (remove).
Why this is hard to do by hand
The DMA's 2025 Email Marketing Report found 22.5% of the average marketing list is a problem: 8% invalid (they will bounce), 6.5% catch-all (mail may be dropped without notice), 4% role-based (more complaints) and 4% inactive for 12 months or more. Most marketing teams don't clean regularly, so they pay ESP fees to mail those addresses, and the damage spreads. When bounces and complaints rise, Gmail and Microsoft throttle your sending and push good mail to spam for the whole list.
Why shrinking your mailing list by 20% pays off
Marketing teams resist cleaning because a smaller list feels like less reach. A 2025 Mailchimp study of 12,000 accounts found senders who removed the worst 20% of their list (invalid, catch-all and chronically unengaged addresses) saw inbox placement rise 28% and revenue per email rise 19% within 30 days. Gmail and Microsoft weight sender reputation by engagement. When a fifth of your list never opens or clicks, the filters read your mail as unwanted and lower placement for everyone, including the subscribers who want it. Remove those addresses and your engagement rate and reputation both go up. The reach math is closer than it looks: 10,000 subscribers at 79% placement reach 7,900 inboxes, and 8,000 at 95% reach 7,600, with far better engagement per send.
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 your mailing list
Upload a CSV exported from Mailchimp, SendGrid, ActiveCampaign or any other ESP. Cleanlist AI finds the email column and starts checking.
- 02
Run the five checks
Every address goes through SMTP, catch-all, disposable, role-based and spam trap checks, at 0.5 credits per address.
- 03
Review the three groups
Every address lands in Safe (send now), Risky (send carefully or suppress) or Invalid (remove), with a count and share for each group.
- 04
Remove or suppress the problem addresses
Delete the invalid addresses. Move the risky ones to a suppression list or a lower-priority segment.
- 05
Re-check the list on a schedule
Re-verify monthly or quarterly, or have an agent do it on a schedule, so newly invalid addresses get caught before they pile up and hurt your sender reputation.
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 |
|---|---|---|
| Verification layers | Basic SMTP check only | 5 layers: SMTP, catch-all, disposable, role-based, spam trap |
| Catch-all domain handling | Marked as valid (false positive) | Detected and flagged |
| Disposable email detection | A basic domain blocklist | Checked on every address |
| Processing 50,000 emails | 30-60 minutes (single-provider tools) | One upload, one batch |
| Works with your ESP | Depends on the tool | Any ESP that exports and imports CSV |
| Cost per verification | $0.003-0.01 per email (single-check tools) | 0.5 credits per email, all five checks |
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 clean 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.
How often should I clean my mailing list?
At least quarterly, and monthly if you send weekly or more. The DMA recommends cleaning before any major campaign, especially when the list hasn't been verified in 60 days. An agent can run the re-verification on a schedule, so nobody has to remember.
What is the difference between cleaning an email list and cleaning a mailing list?
Mostly the same thing. Mailing list cleaning usually means marketing subscribers and adds engagement risk: valid addresses unlikely to open, which drag your open rate down. Email list cleaning is the broader term and covers sales lists and CRM exports too. Cleanlist AI runs the same five checks on both.
Will cleaning my mailing list reduce my subscriber count?
Yes. Removing invalid and risky addresses shrinks the list, and everyone left on it is deliverable. Your mail then reaches real inboxes without bounces and complaints dragging down your sender reputation. We don't publish an open-rate lift, so measure yours before and after.
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.