Excel vs CSV: Which Should You Use for Data?

Excel and CSV look similar, but they behave very differently. Here is when to use each.

The short answer. Use CSV to move data between systems and to load databases. Use Excel (.xlsx) when people will read, format or share the file.

What each stores. A CSV is plain text with no formatting, formulas or types. An .xlsx file keeps several sheets, formatting, formulas and column types. Because CSV has no types, Excel may change values when it opens one: leading zeros are dropped, long numbers become 1.23E+15 and some text turns into dates.

Size and speed. The same 100,000-row table is 6.87 MB as CSV and 4.41 MB as Excel, because an .xlsx file is compressed inside. Writing the Excel file took about 1.1 seconds in our test, compared with about 0.1 seconds for the CSV conversion. Gzip shrinks the CSV to 1.41 MB but the Excel file only to 4.20 MB.

Converting safely. To keep zeros and dates right, convert CSV to Excel instead of double-clicking the CSV. To load a spreadsheet into a database, convert Excel to CSV. Data Utility does both in your browser without uploading the file.

Open the CSV to Excel converter

Related tool pages

  • JSON, CSV, Parquet and Excel Converter: Convert between JSON, CSV, Parquet and Excel online for free, one file or a whole folder. It runs in your browser, so nothing is uploaded.
  • JSON to CSV Converter: Convert JSON to CSV online for free. Drop a file or paste data, click convert and download. It runs in your browser, so your data is never uploaded.
  • CSV to JSON Converter: Convert CSV to JSON online for free. Drop a file or paste data, click convert and download. It runs in your browser, so your data is never uploaded.
  • CSV to Parquet Converter: Convert CSV to Parquet online for free. Drop a file or paste data, click convert and download. It runs in your browser, so your data is never uploaded.
  • JSON to Parquet Converter: Convert JSON to Parquet online for free. Drop a file or paste data, click convert and download. It runs in your browser, so your data is never uploaded.
  • Parquet to CSV Converter: Convert Parquet to CSV online for free. Drop a file or paste data, click convert and download. It runs in your browser, so your data is never uploaded.

How to use the CSV to Excel converter: step by step

  1. Open the CSV to Excel converter.
  2. Drop in your CSV file.
  3. Convert and download the .xlsx file.
  4. Open it and check the columns.

When to use the CSV to Excel converter

  • Choose a format for a report
  • Stop Excel changing your IDs
  • Prepare a spreadsheet for a database
  • Share data with a colleague

Example

Input: id,name,age 1,Ada,36 2,Alan,41

Output: A Excel file with the same columns (id, name, age) and typed values.

Frequently asked questions

How do I convert CSV to Excel?

Drop your CSV file (or paste the data), check the options, click Convert and download the Excel result.

How big can a file be?

It depends on your device. A few hundred MB usually works.

Which conversions does the Format Converter support?

Any direction between JSON, CSV, Parquet and Excel (.xlsx), for one file or a whole folder. Nested JSON is flattened into columns such as address.city. For Excel, the first sheet is read; old .xls files are not supported.

Why did my number or date change after converting?

Types are detected from the values. Turn off "Detect types" to keep everything as text, which also keeps leading zeros in IDs and phone numbers.

Tip: Keep IDs and phone numbers as text when you convert, so zeros are not lost.