Browser-local tool · No AI model required
CSV Cleanup & Check
Find exact duplicate records, blank cells and rows, outer whitespace and inconsistent column counts. Choose changes, review a preview, then approve your export. Your source file is never overwritten.
This tool reads and processes the selected file in browser memory. Its file-processing code does not send file contents to a server, analytics or logs. The surrounding site may load assets and make ordinary site requests. Browser extensions and downloaded files are outside this tool’s control. Reset clears the working data from this tool’s state; downloaded files remain on your device.
1. Choose a CSV or try the demo
UTF-8, comma-separated CSV only. Maximum 1 MiB, 5,000 records including the header, 100 columns and 100,000 cells. The first record is treated as the header and never removed.
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What this check can and cannot decide
Use the synthetic demo to see a duplicate, whitespace around a name, a blank row, an uneven row and a formula-risk cell. Nothing is removed on import. Cleanup is deterministic: no account, paid AI call or model judgment is needed.
A duplicate row might represent a legitimate repeated transaction. Review the source before removing it. A date such as 03/04/2026 stays exactly as supplied; the tool cannot know the intended locale. IDs such as 0001 and ZIP codes such as 00123 remain strings. It does not change case, infer types, merge similar names or fill blanks.
Quoted commas, escaped quotes, embedded newlines, CRLF/LF/CR record endings and a UTF-8 BOM are supported. Semicolon or tab-delimited files are not auto-detected; export them as comma-separated UTF-8 first. A one-column CSV is valid. Empty files and malformed quoting are rejected rather than silently repaired.
Compare your before-and-after files with Moyan AI Work Check. For a complete worked example with independent spreadsheet checks, read Clean a messy CSV with AI. For broader checking habits, use Verify AI output. This tool complements those guides; it does not resolve their ambiguous business rules.