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Convert CSV to XLSX - Turn Raw Data Into Excel Spreadsheets

Transform plain CSV files into full-featured Excel spreadsheets. Add formatting, formulas, and more.

Step 1: Upload your files

You can also Drag and drop files.

Step 2: Choose format
Step 3: Convert files

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Your CSV Data Deserves Better

You have data in a CSV file. It opened in Excel as a mess of plain text with no formatting, or worse, columns didn't separate properly. Now you need to share it with colleagues or use it in a report.

Converting CSV to XLSX transforms your raw data into a proper Excel spreadsheet. You get clean columns, the ability to add formatting, and access to all of Excel's features like formulas, charts, and filters.

How to Convert CSV to XLSX

  1. Upload your CSV file - Drag and drop or click to select your comma-separated file
  2. Convert to XLSX - We parse your data and create a proper Excel spreadsheet
  3. Download your Excel file - Open in Excel, Google Sheets, or any spreadsheet app

The entire process takes seconds. Your data structure is preserved with columns properly separated.

Why Convert CSV to Excel Format?

CSV files are plain text. They store data, nothing more. In our testing, users most commonly convert to XLSX for these reasons:

  • Formatting - Add colors, bold text, borders, and number formatting to make data readable
  • Formulas - Use SUM, AVERAGE, VLOOKUP, and thousands of other Excel functions
  • Multiple sheets - Organize related data across tabs in one workbook
  • Charts and graphs - Visualize your data without importing elsewhere
  • Filters and sorting - Analyze large datasets with built-in tools
  • Professional appearance - Share polished spreadsheets instead of raw data

CSV vs XLSX: Key Differences

Understanding when to use each format helps you work more efficiently.

FeatureCSVXLSX
Data storagePlain textStructured XML
FormattingNoneFull support
FormulasNot supportedFull support
Multiple sheetsNoYes
Charts/graphsNoYes
File sizeSmallerLarger
Universal compatibilityAny text editorSpreadsheet apps

CSV is ideal for data exchange between systems. XLSX is better when you need to analyze, format, or present that data.

Common Use Cases

Database Exports

Most databases export to CSV format. Converting to XLSX lets you analyze the data with pivot tables, apply conditional formatting to highlight trends, and create charts for presentations.

Financial Reports

Raw transaction data from accounting software comes as CSV. Excel format allows you to add formulas for totals, format currency properly, and create professional reports for stakeholders.

CRM and Marketing Data

Customer lists and campaign data exported from tools like Salesforce or Mailchimp arrive as CSV. In Excel format, you can segment contacts, calculate metrics, and build visualizations.

Scientific Data

Research instruments and data loggers output CSV. Converting to XLSX enables statistical analysis, chart creation, and proper documentation with multiple sheets for methodology notes.

What Happens During Conversion

When we convert your CSV to XLSX:

  • Commas (or other delimiters) are recognized and data splits into proper columns
  • Column widths adjust to fit your data
  • Text and numbers are stored in appropriate cell formats
  • The file structure changes from plain text to Office Open XML format

Your data integrity is preserved. What you had in CSV appears correctly in the XLSX spreadsheet.

Works in Your Browser

No software installation required. Convert CSV to XLSX on any device:

  • Windows, Mac, Linux, Chromebook
  • Chrome, Firefox, Safari, Edge
  • Tablets and phones (though spreadsheet editing is easier on desktop)

The converted XLSX file opens in Microsoft Excel, Google Sheets, LibreOffice Calc, Apple Numbers, and any other spreadsheet application.

Alternative Conversions

Depending on your needs, other formats might work better:

  • CSV to XLS - Older Excel format, compatible with Excel 2003 and earlier
  • CSV to PDF - When you need to share data that shouldn't be edited
  • CSV to HTML - Display data on web pages

XLSX remains the best choice for most spreadsheet work due to its balance of features and compatibility.

Pro Tip

Before converting large CSV files, check the encoding. UTF-8 is safest for special characters. If you see garbled text after conversion, the original CSV likely uses a different encoding like Windows-1252 or ISO-8859-1.

Common Mistake

Opening CSV directly in Excel instead of converting. Excel often strips leading zeros from product codes and ZIP codes, converts long numbers to scientific notation, and mangles dates. Proper conversion preserves your data as-is.

Best For

Database exports that need analysis, formatting, or presentation. When you have raw data that requires formulas, charts, pivot tables, or simply needs to look professional for sharing.

Not Recommended

If you're just transferring data between systems, keep it as CSV. Converting to XLSX adds unnecessary complexity for pure data exchange. Only convert when you need Excel's features.

Frequently Asked Questions

Yes. The converter properly parses comma-separated values and places each field in its own column. Your data structure is preserved exactly as it was in the original CSV file.

Our converter handles various delimiters automatically. Whether your file uses commas, semicolons, tabs, or pipes as separators, the data will be correctly split into Excel columns.

Yes. Once converted, your file is a full Excel spreadsheet. You can add formulas, create charts, apply formatting, use pivot tables, and access all other Excel features.

Browser-based conversion works well for files up to several hundred MB. For extremely large CSV files with millions of rows, you may experience slower processing times.

XLSX is the modern Excel format introduced in 2007. It's smaller, more secure, and supports more rows (1 million vs 65,000). XLS is the older binary format needed only for compatibility with Excel 2003 or earlier.

Yes, if your CSV is UTF-8 encoded (most modern exports are). Special characters, accented letters, and non-Latin scripts all transfer correctly to the XLSX file.

Yes. Upload multiple CSV files and batch convert them all to XLSX. Each CSV becomes its own Excel workbook. This is useful when processing multiple database exports or reports.

No. XLSX files open in any modern spreadsheet application including Google Sheets (free), LibreOffice Calc (free), Apple Numbers, and WPS Office. Microsoft Excel is just one option.

Yes. The conversion happens in your browser. Your CSV data is not uploaded to any server. The file processing occurs locally on your device, keeping your data private.

You can, but Excel sometimes misinterprets CSV data. Dates may convert incorrectly, leading zeros get stripped from numbers, and column separation can fail. Converting through our tool avoids these common issues.

Quick access to the most commonly used file conversions.