Convert XLS to CSV
Converting XLS to CSV strips a spreadsheet down to its raw data so it can be imported into databases, analytics tools, and programming scripts. CSV is the universal exchange format for tabular data: a plain-text file where each line is a row and commas separate the columns. Almost every data tool, from Python and R to SQL databases and web applications, reads it without special handling, which is why it is the format you reach for when moving data out of a spreadsheet and into something else.
The trade-off is that CSV holds only the cell values. Everything that makes XLS a spreadsheet rather than a grid of text, formulas, formatting, charts, and multiple worksheets, is discarded in the conversion. Knowing exactly what survives and what does not prevents the surprises that show up after import, and avoiding the encoding and delimiter pitfalls below is the difference between a clean import and a file full of garbled characters or misaligned columns.
This guide explains exactly what is kept, what is lost, the encoding and delimiter pitfalls that cause most import errors, and how to convert in the browser.
What is XLS?
XLS is Microsoft Excel's spreadsheet format. The original .xls is the legacy binary format from Excel 97-2003; the modern .xlsx, from Excel 2007 onward, is a smaller XML-based version. Either way, a spreadsheet is far more than data: it holds formulas that calculate values, formatting and colors, charts, pivot tables, and often several worksheets in one file.
That richness is exactly why converting to CSV is a reduction rather than a simple copy. CSV cannot represent a formula, a chart, or a second worksheet, so the conversion keeps the values and drops the machinery around them. If you need to preserve formulas and formatting, you keep the XLS; you convert to CSV specifically when a downstream tool wants the raw data and nothing else.
What is CSV?
CSV (Comma-Separated Values) is the simplest possible table format: a plain-text file where each line is a row and commas separate the fields. It has no formatting, no formulas, and no concept of multiple sheets, which is precisely what makes it universal. Any spreadsheet app, database, or programming language can read it, and the files are tiny because they contain nothing but the data.
This simplicity makes CSV the standard for moving data between systems: importing into a database, loading a dataset into Python or R, feeding a web application, or exchanging records with another team. When a tool says it accepts a "data import," CSV is almost always the format it means.
What Survives the Conversion and What Does Not
CSV is plain text: rows of values separated by commas, with no concept of formatting or structure beyond the grid. Knowing what disappears prevents nasty surprises after import.
| In your XLS | In the CSV |
|---|---|
| Cell values (text, numbers, dates) | Kept |
| Formulas | Replaced by their last calculated value |
| Multiple worksheets | Only one sheet per CSV; export each separately |
| Formatting, colors, fonts | Lost |
| Charts, images, pivot tables | Lost |
| Merged cells | Flattened; value lands in the top-left cell |
Encoding and Delimiter Pitfalls
Most "my CSV is broken" problems come from two settings:
- Encoding: save as UTF-8 so accented characters, currency symbols, and non-Latin text survive. A CSV saved in a legacy regional encoding often shows garbled characters when opened elsewhere.
- Delimiter: in regions that use a comma as the decimal separator, spreadsheet apps export with a semicolon delimiter instead of a comma. If your target tool expects commas, set the delimiter explicitly or convert with a tool that defaults to comma-separated UTF-8.
- Quoting: values that contain commas, quotes, or line breaks must be wrapped in double quotes. A correct exporter does this automatically; a manual rename of .xls to .csv does not and will corrupt those rows.
- Leading zeros and long numbers: codes like ZIP codes or IDs can lose leading zeros or shift to scientific notation. Format the column as text before export if those values matter.
Why Convert XLS to CSV?
Importing into a database
Databases and data-loading tools expect a plain, predictable table, not a spreadsheet with formulas and formatting. CSV is the format almost every database import wizard and bulk-load command accepts directly, which makes it the natural bridge from Excel into a database.
Analysis in Python, R, or other tools
Data-science libraries read CSV in a single line of code. Converting your spreadsheet to CSV lets you load it straight into pandas, R, or a notebook without wrestling with Excel-specific quirks, so the data is ready for analysis immediately.
Sharing data across systems
CSV is the lowest common denominator for tabular data. When you need to hand a dataset to another team, another application, or a partner who may not use Excel, CSV is the format everyone can open and process without compatibility headaches.
Smaller, simpler files
Because CSV stores nothing but the values, the files are far smaller than the equivalent spreadsheet and contain no hidden formulas or metadata. That makes them faster to transfer and easier to inspect, version, and diff in plain text.
How to Convert XLS to CSV
Upload XLS
Select your XLS file.
Choose CSV output
Select CSV as your output format.
Convert
Click convert. The first sheet will be exported as CSV.
Download CSV
Save your CSV file for use in databases and data tools.
Convert in the Browser, No Upload
The FileFormer document converter turns XLS and XLSX into clean, UTF-8 CSV directly in your browser, with correct quoting so values containing commas stay intact. Because it runs on your device, the spreadsheet, which may hold customer or financial data, is never uploaded to a server.
Ready to Convert XLS to CSV?
Use our free online converter. No signup, no watermarks, practical limits.
Convert XLS to CSVPro Tips
Only first sheet exports
CSV exports only one sheet. Export multiple sheets separately if needed.
Formulas become values
XLS formulas are converted to their calculated values in CSV.
Check encoding
Use UTF-8 encoding for CSV to ensure international characters display correctly.
Frequently Asked Questions
Does XLS to CSV lose data?
Formulas become values, formatting is removed, and only one sheet can be exported. All actual data values are preserved.
Can I import CSV into Python?
Yes, use pandas: pd.read_csv('file.csv') to import CSV data into Python for analysis.
What is the difference between XLS and CSV?
XLS is a full spreadsheet format with formulas and formatting. CSV is plain text with only data values.
How do I import CSV into MySQL?
Use LOAD DATA INFILE or MySQL Workbench's import wizard to import CSV files into MySQL.
Will international characters work in CSV?
Yes, if you export with UTF-8 encoding. Make sure your importing application also reads UTF-8.
Why does my CSV open as one column or with semicolons?
Your spreadsheet exported with a semicolon delimiter, common in locales that use a comma as the decimal mark. Re-export choosing a comma delimiter, or open the file with the delimiter set explicitly, so each value lands in its own column.
How do I convert just one sheet of a multi-sheet workbook?
CSV holds a single table, so each worksheet becomes its own CSV. Select or export the sheet you need; the others are saved as separate files rather than combined into one.