Free Tool

CSV Cleaner

Deduplicate, merge, split, and filter your CSV files. 100% browser-based, your data never leaves your device.

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

Yes, the CSV Cleaner is completely free to use. All processing happens in your browser - we don't store or upload your data.

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.

You can process files up to 100MB. For larger files, we recommend splitting them first using our Chunker feature, then processing each chunk.

Our database contains 4,768 personal/free email domains including Gmail, Yahoo, Hotmail, and regional providers from around the world.

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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