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Clean up a spreadsheet in a few clicks

Open a CSV or paste rows from a spreadsheet. Remove duplicates and empty rows, trim stray spaces, split or merge columns and fix dates, then save it.

CSV cleaner

Load your data, apply the fixes you need, then save.

No data loaded Open a CSV, paste rows above and press Load, or try the example.

Your data is cleaned in this browser tab and never uploaded. Tidy up a messy spreadsheet or CSV file: trim spaces, remove blank and duplicate rows, split and merge columns, fix dates and change letter case, then save it again. It is free and private.

How to clean a CSV file

  1. Press Open a CSV, or paste cells into Paste CSV and press Load. Try an example loads sample data.
  2. Tick First row is a header if the first row has column names.
  3. Under Clean up, choose Trim spaces, Remove empty rows or Remove duplicate rows. You can Ignore upper and lower case when matching.
  4. Use Split to break a column apart, at spaces, commas, semicolons, dashes, slashes or at @. Use Merge to join columns with a space, comma, dash or nothing.
  5. Use Fix dates, Title Case, UPPER CASE or lower case, or Remove the column, then press Apply.
  6. Press Undo to step back, or Back to the original to start over.
  7. Press Save CSV or Save Excel.

What each fix does

Trim spaces removes spaces at the start and end of every cell and turns double spaces into single ones, so “Ana  Diaz ” and “Ana Diaz” match. Remove duplicates keeps the first of any rows that are the same, across all columns or by one column such as email. Split turns one column into several, and merge joins two into one. Every step can be undone, and the original stays one click away.

Fixing dates

Fix dates reads dates written in many ways, such as 3/14/24, 14.03.2024, 3 March 2024 or March 3rd, 2024, and writes them all the same way. When a date like 03/04/2024 could mean either March or April, the order is worked out from the other dates in the column. If it cannot be, those cells are left as they were and counted, so you can pick day first or month first yourself.

Choose the way dates are written: As 2024-12-31, As 31/12/2024 or As 12/31/2024.

Opening and saving

Open a CSV or TSV file, or copy cells straight from Excel, Numbers or Google Sheets and paste them in. Commas, tabs and semicolons are detected for you. Save as CSV for other apps, or as an Excel file. The preview shows the first 200 rows, and every row is cleaned and saved.

Tips for tidy data

  • Clean a copy. Keep the original file untouched.
  • Trim spaces before removing duplicates, so near matches are caught.
  • Remove duplicates by email or ID column when the other columns may differ slightly.
  • Check the date format your next program expects before you fix dates.
  • Scan the preview after each step so mistakes are easy to undo.

Who uses it

Small businesses tidying a mailing list, students preparing survey data, office workers merging exports from different systems, and freelancers cleaning a client's spreadsheet. To turn clean data into a graph, try CSV to chart.

Questions

Is my data uploaded?

No. It is cleaned in your browser tab and never sent anywhere.

Why did the names get mangled?

Check the file was opened with the right separator, and that the first row is set as a header only when it holds column names.

How big a file can it open?

Large files work, though very big ones take longer and use more memory. The preview shows the first 200 rows only, and all rows are cleaned.

Where to next

Carry on with what you just made, still on your device.

JSON formatterFormat JSON with spaces or tabs, minify it, sort keys and browse it as a tree.JSON validatorCheck whether JSON is valid and see the line, column and a plain explanation of any error, like a trailing comma.JSON to CSVTurn a JSON list of objects into CSV for Excel or Google Sheets.CSV to JSONConvert CSV or spreadsheet cells to JSON.

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