CleanMySheet guide
CleanMySheet cleans CSV files entirely in your browser. Drop a file, review a scan of issues, apply presets (trim, dates, duplicates, names, phones), then export. Strict mode is on by default so column samples never leave the device.
Steps #
- Drop a .csv file or try the sample dataset
- Read the scan: duplicates, dates, phones, empties
- Apply recommended presets or search for a fix
- Preview Original, Cleaned, and Diff
- Download CSV (free up to 500 rows) plus a recipe and quality report
What “clean CSV” actually means #
A messy CSV usually has extra spaces, mixed date formats (03/14/22 vs March 14 2022), duplicate contacts, N/A placeholders, and names in Last, First order. Cleaning is applying reversible, named operations—not asking a chatbot to rewrite your rows. CleanMySheet records why each cell changed.
Why not paste the file into ChatGPT? #
Large language models can invent values, drop rows, or reformat columns inconsistently. They also require you to send data to a server. CleanMySheet uses deterministic rules first (dates, numbers, trim, dedup). Optional AI classification sends only column samples, and only if you turn Strict mode off.
CSV vs Excel #
The same engine parses CSV (PapaParse) and Excel/XLSX (SheetJS), including Excel serial dates and multiple sheets. If you have an .xlsx, use the clean Excel workflow; the recipe still exports as CSV for the MVP.
Related searches this page answers #
- clean csv online
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- csv data cleaning tool