Verify Your Email List in Seconds
Verify Your Email List with Cleanlist's waterfall enrichment. Upload a CSV or connect your CRM. Every new workspace opens on Scale for 14 days: 250 credits, 3 seats, no card.
Run a live syntax, MX, and deliverability check in seconds. No signup required.
Verify an email freeHow does Cleanlist verify your email list in seconds?
Cleanlist runs every address through a multi-layer verification pipeline: SMTP handshake, MX record validation, catch-all domain detection, disposable email filtering, and role-based address flagging. Unlike single-check tools, our waterfall approach queries multiple verification engines so catch-all domains, which represent 12-18% of B2B inboxes, are identified instead of marked as 'valid' by default.
Why this is hard to do by hand
Sending campaigns to an unverified email list is like mailing letters to abandoned buildings. ESPs track your bounce rate in real time, and once it crosses 5%, your entire sending domain can be throttled or blocklisted. The worst part: most marketers discover the damage after a campaign has already gone out, when inbox placement for the rest of their list has already dropped by 20-30%.
Catch-All Domains Are the Blind Spot in B2B Email Verification
12-18%of B2B domains are configured as catch-all
Catch-all mail servers accept every address at the SMTP level, whether the mailbox exists or not. Traditional verification tools see the 'accepted' response and mark the address as valid. But in practice, many catch-all domains silently discard mail to non-existent addresses, resulting in soft bounces that accumulate over time and erode sender reputation. Cleanlist's internal data from verifying 4.2 million B2B addresses in Q1 2026 shows that 12-18% of corporate domains are configured as catch-all. Among those, roughly 35% of tested addresses were actually undeliverable. By cross-referencing verification results from multiple engines and analyzing historical delivery patterns, Cleanlist identifies catch-all addresses that are likely to bounce, reducing undetected false positives by an estimated 60% compared to single-provider verification.
Source: Cleanlist verification pipeline data, Q1 2026 (4.2M addresses processed)
Pay for the result, not the lookup
Cleanlist walks 25+ providers in cost order on a single lookup and charges once for what comes back. A verified work email is 1 credit, a direct dial is 10, both together are 11, validation is 0.5 and AI qualification is 5. A lookup that finds nothing costs nothing, and every seat draws on one shared team wallet.
- 98%Email deliverability
- <2%False positive rate
- 90sPer 10K emails
- 25+Providers queried in cost order on a single lookup
- 98%Verified work email on a 500-lead stratified benchmark
- 85%Direct dial on that same 500-lead test
- 0Credits to search. Free and unlimited on every plan
How It Works
- 01
Upload Your Email List
Drag and drop a CSV or paste emails directly. Cleanlist auto-detects the email column and handles messy formatting, extra spaces, mixed cases, and trailing characters are normalized automatically.
- 02
Syntax & Domain Pre-Check
Obvious invalids (typos like gmial.com, missing @ signs, localhost domains) are flagged instantly before any credits are used. MX records are resolved to confirm the domain can actually receive mail.
- 03
Multi-Provider SMTP Verification
Each remaining address is verified through multiple SMTP verification engines in sequence. If Provider A returns an ambiguous result, Provider B confirms or denies delivery, eliminating false positives.
- 04
Catch-All & Disposable Detection
Domains configured as catch-all (they accept any address at the server but silently discard invalid ones) are flagged with a risk score. Temporary and disposable email services like Guerrilla Mail and Mailinator are identified and separated.
- 05
Risk Scoring & Categorization
Every address receives a deliverability score: Safe, Risky, or Invalid. Role-based addresses (info@, sales@, support@) are tagged separately so you can decide whether to include them in outreach.
- 06
Download Verified List
Export your cleaned list as CSV with verification status columns, or push safe addresses directly to your ESP. The original file structure is preserved, only verification data is appended.
Key Benefits
98% Email Accuracy
Real-time email verification catches bounces, catch-alls, and disposable addresses before they cost you.
25+ data providers
Waterfall enrichment across multiple providers means higher match rates than any single-source tool.
No Code Required
Upload a CSV, connect your CRM, or use the API. Works however your team prefers.
14-Day Scale Trial
250 credits and 3 seats for 14 days. No credit card, no sales call, no commitment.
Manual Process vs Cleanlist
| Feature | Manual | Cleanlist |
|---|---|---|
| Catch-all domain handling | No detection, marked as valid | Multi-engine catch-all detection with risk scoring |
| Verification speed (10K emails) | 6-12 hours with a free tool | Under 90 seconds |
| False positive rate | 15-20% (single SMTP check) | Under 2% (waterfall cross-check) |
| Disposable email detection | Not included in most free tools | 200K+ disposable domains tracked |
| Role-based address flagging | Manual regex filtering | Automatic tagging with send/skip recommendation |
| ESP reputation protection | Reactive, fix after bounce spike | Proactive, remove risky addresses before sending |
Frequently Asked Questions
How accurate is Cleanlist's data?
Cleanlist achieves 98% email accuracy through real-time verification and cross-referencing across 25+ data providers. Every record is validated before delivery.
What do I get when I sign up?
Every new workspace opens on Scale for 14 days: 250 credits, 3 seats, no credit card, and every feature except the public API and MCP. After the trial the Free plan is $0 for 30 credits a month. Each credit processes one record (enrichment, verification, or lookup).
What data providers does Cleanlist use?
Cleanlist uses waterfall enrichment across 25+ providers including major B2B data sources. The system automatically selects the best provider for each record to maximize match rates.
Can I connect my CRM?
Yes. Cleanlist integrates with HubSpot, Salesforce, and other CRMs. Enriched data syncs back automatically. You can also upload CSV files or use the REST API.
How long does it take to verify my data?
Most jobs complete in under 2 minutes for up to 10,000 records. Larger files are processed in batches with progress updates.
What happens to catch-all emails during verification?
Catch-all domains accept all addresses at the server level, making SMTP verification unreliable. Cleanlist flags catch-all addresses separately with a risk score based on domain reputation, mail server behavior, and historical bounce data across our provider network. You can choose to include low-risk catch-alls or exclude them entirely.
How often should I re-verify my email list?
B2B email lists degrade at roughly 2% per month due to job changes and domain deactivations. We recommend re-verifying before every major campaign, or setting up monthly scheduled verification through Cleanlist's API to catch decayed addresses before they affect deliverability.
Does verification work on free email providers like Gmail and Outlook?
Yes. Cleanlist verifies addresses on all major providers including Gmail, Outlook, Yahoo, and iCloud. However, some providers rate-limit SMTP checks, Cleanlist's multi-provider waterfall routes around rate limits to maintain accuracy even on high-volume lists.
Gain full access for 14 days.
Upload a CSV or connect HubSpot, Salesforce or Pipedrive. Searching costs nothing, and a lookup that finds nothing costs nothing.
No card to start. Every new organization gets fourteen days on Scale with 250 credits and three seats, every feature except the public API and MCP. The Free plan stays at 30 credits a month after that.
Gain full access for 14 days.
250 credits, 3 seats, no card needed. Access to every feature except public API & MCP.