SpreadsheetFix

Clean a CSV and get an Excel-ready file

Opening a raw export in Excel usually means mangled dates, blank rows and columns full of stray spaces. Upload the CSV here, let SpreadsheetFix fix it, and download a tidy file that opens cleanly in Excel.

Free up to 5,000 rows · No sign-up · Nothing uploaded

Drag & drop your file

or click to browse — CSV, TSV, XLSX up to 50MB

100% client-side. Your data never leaves your browser.

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Before and after

Before
Customer Name ,Signup Date,Notes,
José Díaz,03/14/2024,,
,,,
Mia Chen ,2024-02-01,,
After SpreadsheetFix
customer_name,signup_date
José Díaz,2024-03-14
Mia Chen,2024-02-01

How it works

  1. 1

    Upload the CSV you’d normally open in Excel.

  2. 2

    SpreadsheetFix repairs garbled characters, trims spaces, tidies headers, normalises dates and removes blank rows and empty columns.

  3. 3

    Download a clean CSV that opens correctly in Excel — or, on Pro, a native .xlsx workbook.

Why Excel mangles CSV files

Excel guesses each column’s type when it opens a CSV. It reads dates using your regional settings, drops leading zeros from codes, and can show accented characters as “é” if the file’s encoding isn’t what it expects. Cleaning the data before it reaches Excel removes most of those surprises.

Free clean CSV, or native XLSX on Pro

Free users download a cleaned CSV that opens directly in Excel. Pro adds one-click .xlsx export, so the file arrives as a real workbook, with no import wizard and no type guessing.

Tidy headers for pivot tables

Header normalisation turns “Customer Name ” into customer_name, so pivot tables, Power Query and formulas reference clean, predictable column names.

Frequently asked questions

How do I convert a CSV to Excel without breaking the dates?

Normalise the dates to YYYY-MM-DD first — SpreadsheetFix does this automatically — and Excel will read them consistently regardless of regional settings. Pro users can export straight to .xlsx.

Is XLSX export free?

Cleaning and CSV download are free for files up to 5,000 rows. Native .xlsx export is part of Pro (€12/month).

Why do accented characters look wrong when I open a CSV in Excel?

Excel may read a UTF-8 file as a legacy encoding. SpreadsheetFix repairs characters that are already garbled, and its CSV export is UTF-8 so Excel can display accents correctly.

Can I upload an Excel file instead?

Yes. SpreadsheetFix accepts .xlsx and .xls as well as CSV and TSV.

Cleaning bigger files every week?

Pro cleans up to 500,000 rows per file, unlocks all 18 rules, exports to Excel and removes the watermark.

See Pro pricing

Related tools

Normalize Dates

Fix mixed date formats in a CSV: 03/04/2024, 4 March 2024 and 2024-03-04 become one format. Detects US vs European order per column. Free, in-browser.

Fix CSV Encoding

Repair garbled characters like é, ’ and ü in a CSV and convert Windows-1252 files to UTF-8. Free, private, runs entirely in your browser.

Trim Whitespace

Remove leading, trailing and double spaces from every cell in a CSV or Excel file, and drop blank rows. Free, instant and private — nothing is uploaded.