Data Cleaner
Remove duplicates, fix nulls, trim whitespace, and standardize formats in one pass. Fast, private, and secure browser-based t
Your files never leave your device. Processed locally. 100% private.
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How To Use Data Cleaner
Complete your task perfectly in just three straightforward steps.
Upload CSV
Drop your CSV file.
Select cleaning operations
Choose from: remove duplicates, fix nulls, trim whitespace, standardize formats.
Download
Download the cleaned CSV file.
FAQ
Everything you need to know about the Data Cleaner.
What cleaning operations are available?
Remove duplicates, fill/remove nulls, trim whitespace, standardize dates, fix number formats, and remove empty rows/columns.
Can I preview changes before applying?
Yes — a before/after diff shows exactly what will change.
Is my file uploaded?
No. Everything runs locally in your browser.
What is the file size limit?
Process files up to the browser memory limit.
Can I run multiple operations in one pass?
Yes — select all needed operations and apply them together.
Is my data private? Does anything get uploaded?
Your data never leaves your device. All cleaning logic runs in your browser using DuckDB WebAssembly — a local SQL engine. No rows, column names, or file contents are transmitted to Refinata's servers or any third party. The AI Smart Suggestions also run locally by analyzing statistical patterns in the data, not by sending data to an AI API. The only network request is downloading the DuckDB WASM binary on first use (approximately 5MB, cached in your browser).
How does the CSV cleaner compare to Excel's built-in tools?
Excel requires manual steps for most of these operations: Remove Duplicates is one click but only removes exact duplicates. Trimming whitespace requires the TRIM() formula applied cell-by-cell. Standardizing null values requires Find & Replace with 6–10 separate runs for each variant (N/A, NULL, none, etc.). Date standardization requires Text-to-Columns or Power Query. Refinata applies all of these simultaneously in a single click, on files of any size, with a detailed change report, and without any server upload.
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