Clean a list
No file handy? Load a sample list (made-up rows on example-style domains).
Preview shows the first 200 rows of each group. Downloads contain every row, with listlint_status, listlint_reasons and the original spreadsheet row number added.
What it checks
Excluded
Missing or invalid emails, disposable domains, your suppression list, duplicate emails, duplicate LinkedIn profiles, and the same person listed twice at one company. The most complete row is kept.
Sent to review
Role mailboxes, free webmail on a B2B list, likely domain typos (with a suggested fix), email domains that don't match the company website, missing names, and contacts over your per-company cap.
Fixed quietly
Spaces, invisible characters, "N/A" and "null" cells, upper-case emails, mailto: prefixes and ALL-CAPS names. Formula-like cells are made safe on export.
What it doesn't do
ListLint checks format and list hygiene. It does not ping mail servers, so it can't prove a mailbox exists. Run a verifier on the clean file for that; you'll spend fewer credits after deduping.
Pricing
Proposed pricing. Billing is not live yet. Everything below is free during early access, with no card and no sign-up. We'll email the waitlist before any paid plan opens.
- Up to 2,000 rows per file (proposed limit)
- All checks and reasons
- No watermark
- Runs in your browser
- Unlimited rows and files
- Saved rule presets per client
- Saved suppression list
- Export presets for Instantly, Smartlead and HubSpot
- Everything in Pro
- 3 seats
- Shared presets and suppression lists across the team
Get early access news
Leave your work email and we'll tell you when Pro features open. No spam, and we never sell or share your email.
Rather email? Write to smurphy@roicpleadgen.com.
FAQ
Is my data uploaded anywhere?
No. Cleaning runs entirely in your browser with JavaScript. Your CSV is never sent to our servers. Only the waitlist form sends data (your email and the list size you pick).
Does it verify that a mailbox exists?
No. It checks syntax, duplicates and risk signals. Mailbox verification needs an SMTP check, which a browser can't do. Dedupe here first, then verify the smaller file.
Which exports does it understand?
It auto-detects common column names, including Apollo-style headers like first_name, organization_name and person_linkedin_url. You'll see which columns it picked before you clean.
Who makes it?
ROICP Lead Gen, a B2B lead-generation and ideal-customer-profile (ICP) company. ListLint is our first free micro tool for the list-hygiene step before any send.