Convert Excel to CSV

Open any XLSX, pick the sheets you want, get clean UTF-8 CSV with formulas evaluated to their values. No upload, no install, no size cap.

Convert an Excel file to CSV

When you'd convert Excel to CSV

Feeding a data pipeline. Most ingestion tools, ETL platforms, and database loaders expect CSV. Sending XLSX into them works only if a wrapper does the conversion first.
Opening an Excel file without Office. If you don't have Microsoft 365 or LibreOffice handy, browser-based conversion is the fastest route to seeing the data.
Batch-extracting many sheets. Some workbooks have one sheet per region or month. Exporting all of them at once into separate CSVs is much faster than clicking through Excel's Save As one sheet at a time.
Stripping formatting. XLSX carries cell colours, conditional formatting, comments, charts. Sometimes you just want the values. CSV is the cleanest way to throw away everything except the data.
Version control. XLSX is binary; CSV is text. If you're checking analyses into git, CSV diffs are readable and XLSX diffs are not.

Worked example: multi-sheet workbook

Say you have a workbook orders_2026.xlsx with three sheets:

orders_2026.xlsx
  Sheet "January"   - 1,200 rows
  Sheet "February"  - 1,180 rows
  Sheet "March"     - 1,302 rows

Drop the file in. The sheet picker shows all three. Tick all, click Export, and you get:

orders_2026_January.csv
orders_2026_February.csv
orders_2026_March.csv

Or, if all three sheets share the same schema, tick the "merge sheets with matching schema" option and get a single orders_2026.csv with all 3,682 rows and an extra _sheet column recording the source sheet name.

Format-specific gotchas

Formulas: value vs text. Cells with =SUM(A1:A10) get exported as the cached result by default. If the workbook was saved with stale results (rare), open it in Excel once and resave. You can switch the export to write the formula text instead if you need that.
Merged cells. Excel allows merging cells across rows or columns. CSV cannot represent that. ExploreMyData places the merged value in the top-left cell of the merged region and leaves the others blank, which is the most common convention. Worth checking if your workbook uses merging heavily.
Hidden rows and columns. Hidden cells are still part of the XLSX. By default they're included in the export. Toggle "skip hidden rows/columns" if you want only what's visible.
Date locale and serial numbers. Excel stores dates internally as serial numbers (days since 1900). The locale determines display. We always export ISO 8601 to remove ambiguity.
Encoding. CSV is just text, but downstream tools differ on what they accept. Default is UTF-8 with a BOM (Excel-friendly). Switch to no-BOM UTF-8 for most Linux/Python tooling.
Workbooks larger than a sheet. XLSX has no real row cap, but a single sheet can theoretically hold up to 1,048,576 rows. For "raw data lake" extracts this is enough; for true big data, stop at the source.

How this differs from the alternatives

vs Convertio, Zamzar, CloudConvert, FreeConvert, ONLYOFFICE. All upload your XLSX (which often contains private business data) to a server. Free tiers cap at 1 to 100 MB depending on the service, and several throttle by daily minutes or free conversions. ExploreMyData reads the file locally with no upload and no metering.
vs TableConvert. Browser-based, comparable privacy, but caps free conversions at 10 MB per file. We don't.
vs pandas (read_excel + to_csv). Standard Python idiom, but requires openpyxl or xlrd installed and you have to script per-sheet handling yourself. ExploreMyData ships a UI for the common cases.
vs csvkit's in2csv. A great CLI: in2csv data.xlsx --sheet "March" > march.csv. Requires Python plus csvkit, and the multi-sheet UX is cumbersome (one shell loop per sheet). ExploreMyData has the same per-sheet picker in a browser tab.
vs Excel Save As CSV. Works, but exports only the active sheet per click and requires a paid Microsoft 365 license. ExploreMyData batches all sheets in one go and is free.
vs Google Sheets. Free, but uploads the XLSX to Google Drive (which means a Google account and Google's data residency), and exports only one sheet per File > Download. ExploreMyData stays local.

Frequently Asked Questions

Can I convert a workbook with multiple sheets at once?

Yes. When you drop an XLSX with multiple sheets, ExploreMyData lists them and lets you export one sheet, several sheets, or all of them. Each sheet writes to its own CSV. You can also merge sheets with the same schema into a single CSV.

Are formulas evaluated to their current values?

Yes. By default we read the cached value Excel saved with the workbook. Formulas don't appear in the CSV; the result they computed does. If you'd rather export the formula text, that's an option in the export dialog.

Does it handle password-protected XLSX files?

If the file is encrypted with a password, you'll be prompted for it when you open the file. The password stays in your browser; nothing is uploaded. We support standard XLSX encryption.

What encoding does the CSV use?

UTF-8 with a BOM by default. The BOM helps Excel and some legacy tools detect UTF-8 correctly. You can switch to no-BOM UTF-8 or other encodings (Latin-1, Windows-1252) in the export dialog if your downstream tool needs it.

How are dates exported?

Excel stores dates as serial numbers internally. ExploreMyData converts them to ISO 8601 (2026-01-15) by default, which most downstream tools parse without ambiguity. You can change the format in the export dialog.

Is there a file size limit?

No fixed cap. We stream the XLSX read via DuckDB-WASM. Files in the hundreds of megabytes work; the limit is your browser's available memory.

Convert your Excel file to CSV

Drop an XLSX, pick sheets, get clean CSV. No upload, no install, no size cap.

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