CSV Cleaner
Deduplicate, merge, split, and filter your CSV files. 100% browser-based, your data never leaves your device.
How do I clean up my CSV file?
Upload your CSV below to remove duplicate rows, merge multiple files, split large files into chunks, or filter out personal email domains. Everything runs in your browser, so your data never leaves your device, and you can download the cleaned file in seconds.
Drag and drop your CSV file here, or click to select
CSV files only • Processed locally in your browser
Why List Hygiene Matters
Before every email campaign, cleaning your list is essential for deliverability. Duplicate emails waste credits, personal emails lower B2B engagement, and oversized files can't be imported.
Remove Duplicates
Stop paying for the same contact twice and avoid annoying recipients with multiple emails.
Filter Business Emails
For B2B campaigns, remove Gmail and Yahoo addresses to focus on decision makers.
Merge Multiple Files
Combine exports from different sources into one master list.
Split for Import Limits
Break large files into chunks that fit your CRM's import limits.
Frequently Asked Questions
Is this tool really free?+
Yes, the CSV Cleaner is completely free to use. All processing happens in your browser - we don't store or upload your data.
Is my data safe?+
Absolutely. All CSV processing happens locally in your browser using JavaScript. Your files never leave your device. We don't upload, store, or have access to your data.
What's the maximum file size?+
You can process files up to 100MB. For larger files, we recommend splitting them first using our Chunker feature, then processing each chunk.
How many personal email domains do you filter?+
Our database contains 4,768 personal/free email domains including Gmail, Yahoo, Hotmail, and regional providers from around the world.
Why should I verify emails after cleaning?+
Cleaning removes duplicates and filters by domain, but can't tell if an email actually exists. Verification checks if the mailbox is real and can receive mail, preventing bounces that hurt your sender reputation.
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Industry-leading email verification with catch-all detection.
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