Convert Excel XLSX spreadsheets to CSV format for data processing and analysis. Clean, comma-separated output ready for import. Free online.
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Checking files and selected output formats.
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XLSX → CSV is the "get this data out of Excel into something else" conversion — importing to a database, a Python pandas notebook, a marketing tool, or another SaaS. Only exports one sheet at a time; multi-sheet XLSX workbooks need one conversion per sheet. Loses formulas (values only), formatting, and cell colours.
CSV is the lowest-common-denominator data exchange format — every spreadsheet app, database, and analytics tool accepts it. Convert to CSV when you need to move tabular data between systems (importing into Google Sheets, uploading to a database, feeding into pandas / R). Loses formulas, formatting, and multi-sheet structure that XLSX preserves.
A spreadsheet conversion moves cells, sheets, and values from one container to another. Knowing what each format keeps — and what it drops — saves a lot of "where did my formulas go" surprises.
Drop the XLSX file above or click to browse. Free-tier uploads are capped at 10 MB — comfortably enough for tens of thousands of rows; Pro handles files up to 1 GB. The filename is preserved and the new extension is appended automatically.
Cell values, columns, and rows are read from the XLSX and written into the CSV structure. When both formats are spreadsheet-native (XLSX, XLS, ODS), formatting, multiple sheets, and formulas are preserved. When the target is CSV — a plain-text grid — the converter exports the values as clean, comma-separated rows that any tool can import.
Your CSV file is ready in seconds. Open it and confirm the columns line up and numbers kept their type. Both the XLSX you uploaded and the CSV output are permanently deleted from our servers within 30 minutes.
Native spreadsheet formats (XLSX, XLS, ODS) store a workbook: multiple sheets, cell formatting, formulas, charts, and data types all live inside one file. CSV stores exactly one thing — a single grid of raw values as plain text. That difference decides what survives the trip.
Converting between two native formats preserves nearly everything. Converting to CSV deliberately flattens the workbook to its data: one sheet, no formulas (their results are kept, not the formulas themselves), no colours or merged cells. That's not a bug — it's exactly why CSV is the universal format for moving data between systems.
=SUM(A1:A9) exports as the computed number, not the formula. Keep the native XLSX as your working copy if you still need to recalculate.Real reasons people run this conversion — grounded in specific problems, not vague benefits.
Most databases, CRMs, and web apps accept CSV as their import format but reject native workbooks. Converting your XLSX to CSV turns a spreadsheet into something a bulk-import tool can actually read, row by row.
A legacy XLS, an Apple Numbers export, or an ODS from LibreOffice doesn't always open cleanly everywhere. Converting to CSV gets the data into a format the recipient's tool handles without formatting errors or "file corrupt" warnings.
Python, R, and command-line tools love plain, predictable input. Converting XLSX to CSV gives a script a clean grid to parse — no proprietary container to decode, no surprise sheets, just the values.
Native workbooks carry formatting, charts, and metadata that inflate size. If all you need is the data, converting XLSX to CSV can cut the file down dramatically — handy for email limits, uploads, or version control.
Accounting platforms, payroll systems, and analytics tools often publish an exact template format for uploads. If they require CSV and your export is XLSX, this conversion is the step between "ready" and "rejected."
When data arrives as a mix of XLS, XLSX, and ODS from different sources, analysis is a headache. Converting everything to a single CSV format first means one consistent input — and you can batch the whole folder in one pass.
Every conversion happens on TLS-encrypted uploads, on isolated per-request workers, with both the source and the result auto-deleted within 30 minutes. No ads, no watermarks on paid tiers, no data mined for training.
Technical comparison of the two formats — useful for deciding which to use, or for confirming what changes during conversion.
| Property | XLSX | CSV |
|---|---|---|
| Full name | Microsoft Excel (Open XML) | Comma-Separated Values |
| Year introduced | 2007 | 1972 |
| Developer / standard body | Microsoft | IBM (informal) |
| MIME type | application/vnd.openxmlformats-officedocument.spreadsheetml.sheet | text/csv |
| File extension | .xlsx | .csv |
| Compression | ZIP-compressed XML | None |
| Color / data depth | N/A | N/A |
| Max dimensions / size | 1,048,576 rows × 16,384 columns | Unlimited |
| Transparency | No | No |
| Animation | No | No |
| Standard / specification | ECMA-376 / ISO/IEC 29500 | IETF RFC 4180 |
| Best for | Modern Excel spreadsheets, data analysis | Data interchange, database imports, ETL pipelines |
XLSX (Excel Open XML Spreadsheet) is the default file format for Microsoft Excel 2007 and later. Built on the Office Open XML standard (ECMA-376, ISO/IEC 29500), it uses ZIP-compressed XML files to store spreadsheet data, formulas, formatting, charts, and pivot tables. XLSX replaced the legacy XLS binary format with a more efficient, recoverable, and interoperable architecture.
XLSX supports over one million rows and 16,000 columns per worksheet, 500+ built-in functions, conditional formatting, data validation, and advanced chart types. The format is natively supported by Microsoft Excel, Google Sheets, Apple Numbers, LibreOffice Calc, and most modern spreadsheet applications. XLSX is the global standard for financial modeling, data analysis, reporting, and business intelligence workflows.
Quick answers about compatibility, quality, metadata handling, and the most common reasons to convert XLSX files to CSV.