Why it matters
- Mixed dates break sorting and filtering in spreadsheets, BI tools, and imports.
- CleanCSV detects date patterns with rules before changing values.
- Standardized ISO dates make downstream processing much safer.
CSV cleanup landing page
Fix Inconsistent Date Formats in CSV
Standardize mixed date formats like YYYY-MM-DD and MM/DD/YYYY into one clean export-ready format.
Upload a messy spreadsheet
Supports CSV, TSV, XLSX, and XLS. Current plan: Free with files up to 1 MB and 5 analyses per day.
How CleanCSV handles it
- Upload the CSV, TSV, or Excel file with date columns.
- Inspect the report to confirm which columns contain multiple date formats.
- Apply the date standardization fix and export the cleaned dataset.
FAQ
What date format does CleanCSV export?
The automatic date fix converts supported patterns to YYYY-MM-DD.
Will unsupported date strings be changed?
No. Only recognized date formats are standardized automatically.
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