Free CSV cleaner

Drop in a messy CSV. It trims, dedupes, and fixes dates — entirely in your browser. Your file never leaves your computer.

Your CSV file Trim extra spaces from every cell Remove exact-duplicate rows Normalize dates to YYYY-MM-DD Fix random casing (jOhN sMiTh → John Smith)

First row is treated as a header — casing is only fixed from row 2 on.

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