Mockaroo
mockaroo.com
Generates realistic fake test data in CSV, JSON or SQL
Free tier
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datablist.com
Spreadsheet built for cleaning and deduplicating messy list exports.
A browser spreadsheet aimed at the specific job spreadsheets are worst at: taking a CRM or lead export with duplicates, inconsistent casing and half-filled columns and turning it into something usable. Fuzzy deduplication across one or several files is the core feature, alongside bulk find-and-replace and formatting rules. It needs an account, and the free plan caps how many items a collection can hold before you upgrade.
AltFTool does this too
If you would rather not leave the site, CSV Lead Cleaner covers the same job here — free, no account, and it runs in your browser.
Open CSV Lead CleanerQuestions
A genuinely usable free tier with paid plans for volume or team features. Requires an account, data is stored on their servers, and the free plan caps items per collection.
Yes. Datablist sends your input to its own servers to process it. That is fine for public material; for anything containing personal data, use one of the on-device tools instead.
Requires an account, data is stored on their servers, and the free plan caps items per collection.
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