Free online PART to XLS converter

A .part file usually means an incomplete Internet download, while .xls is a finished Microsoft Excel workbook. The practical trigger is often an interrupted spreadsheet download: resume it first, then save or convert the completed payload as XLS.

What the PART format is

.part is generally a temporary filename used while a browser or download manager receives a file. Mozilla Firefox and several download tools create PART files; Chromium-based browsers commonly use .crdownload instead.

PART is not a spreadsheet format and does not define columns, worksheets, formulas, or a conversion method. The file may contain only part of an XLS workbook, or it may be a partially downloaded PDF, archive, installer, or another Internet file. Its original format can sometimes be inferred from the download name, source URL, file size, or file-signature inspection, but changing the extension does not repair missing data.

What the XLS format is

.xls is the Microsoft Excel 97–2003 binary workbook format. It stores worksheets, cell values, formulas, formatting, charts, and some workbook metadata in a form supported by Microsoft Excel, LibreOffice Calc, and other spreadsheet applications.

XLS is useful when a recipient or older business system requires the legacy Excel format. It has lower compatibility with newer Excel features than .xlsx and a maximum of 65,536 rows and 256 columns per worksheet.

How to actually convert PART to XLS

Resume the download first

1. Open the browser or download manager that created the file and use its resume function.
2. Wait until the download finishes. The program should remove .part and restore the original filename, often ending in .xls or .xlsx.
3. Open the resulting workbook in Excel or LibreOffice Calc and verify that worksheets, formulas, and the final rows are present.

If the PART file is already complete

A completed file can occasionally retain the temporary extension after a crash or manual copy. Check its likely type before renaming it. On Linux or macOS, run file download.part; on Windows, inspect the original download name and open a copy in a spreadsheet application rather than the only copy.

If the payload is confirmed to be an XLS workbook, rename download.part to download.xls. Renaming changes only the filename; it does not convert or repair the contents.

If the payload is an XLSX workbook, keep or restore the .xlsx extension, open it in LibreOffice Calc, then choose File → Save As, select Excel 97–2003 (*.xls), and save. In Microsoft Excel, use File → Save As and select Excel 97-2003 Workbook (*.xls).

Using the built-in online converter

You can convert a completed, valid file on 101convert.com for free without installing software. Upload the file only after the download has finished; an incomplete PART file cannot be reconstructed by a converter. If the service does not identify the file, restore its real extension first, because PART provides no reliable format information.

Quality and compatibility limitations

An interrupted PART file is missing bytes, so no conversion tool can reliably recover its workbook structure or data. A file that opens with warnings may have lost formulas, formatting, worksheets, or the workbook index even if some cells remain readable.

Saving XLSX or another spreadsheet format as XLS can remove features unsupported by the older format, including some newer formulas, tables, styles, external connections, and worksheet dimensions. Keep the original completed download and inspect the converted workbook after saving.