Which delimiters are supported?

Comma, semicolon, tab and pipe. Auto-detect looks at the first data line and picks the most frequent candidate; if your file is unusual, set the delimiter explicitly.

Do leading zeros survive?

Yes. A value like 00420 is stored as text, not converted to the number 420 — only values that read back exactly unchanged become numeric cells.

Is there a size limit?

The output must fit an Excel sheet: at most 1,048,576 rows and 16,384 columns. Files beyond that are refused with a clear message.

Is my data uploaded to a server?

No. The .xlsx file is assembled entirely in your browser — your data never leaves your device.

Convert CSV to Excel (XLSX)

Select a .csv file and get a genuine Excel workbook that opens in Excel, Google Sheets, Numbers and LibreOffice. The delimiter is auto-detected (or pick it yourself), quoted fields and embedded commas are handled per the CSV standard, and values that are exact numbers become numeric cells while everything else stays text. Nothing is uploaded to Filesvo.

or drag and drop a .csv file here

Processed on your device — files are never uploaded to Filesvo.

How to use Filesvo

Select or drop a .csv file.
Pick the delimiter, or leave it on auto-detect.
Click Convert to Excel and download the .xlsx file.

How values are typed

A value becomes a numeric Excel cell only when the number reads back exactly as it was written — 42, -3.5, 0.001. Anything that would change on the round trip stays text: 007 keeps its leading zeros, 1e3 is not rewritten as 1000, and long IDs are not truncated to scientific notation. That's a deliberate honesty rule — the spreadsheet shows what your CSV said.

The workbook is written in the standard Office Open XML format — the same container real .xlsx files use — with your data on a single sheet named Sheet1. Multi-line quoted fields, Unicode text and embedded quotes all survive intact.

Transparency handling

Everything lands on one sheet, as values only — this tool doesn't create formulas, styles or multiple sheets.

Private by design

Your files are processed directly in your browser using open-source engines that run in your browser and are not uploaded to Filesvo. Nothing is stored on our servers, because nothing ever reaches them.

Frequently asked questions

Which delimiters are supported?: Comma, semicolon, tab and pipe. Auto-detect looks at the first data line and picks the most frequent candidate; if your file is unusual, set the delimiter explicitly.
Do leading zeros survive?: Yes. A value like 00420 is stored as text, not converted to the number 420 — only values that read back exactly unchanged become numeric cells.
Is there a size limit?: The output must fit an Excel sheet: at most 1,048,576 rows and 16,384 columns. Files beyond that are refused with a clear message.
Is my data uploaded to a server?: No. The .xlsx file is assembled entirely in your browser — your data never leaves your device.

Excel to CSV Converter

Extract any sheet of an .xlsx workbook as clean CSV — entirely in your browser.

CSV to JSON Converter

Turn CSV data into JSON — paste or upload, pick the delimiter, get an array of objects. Runs entirely in your browser.

JSON to CSV Converter

Turn a JSON array of objects into CSV with proper quoting — entirely in your browser.