How to convert XLSB to XLSX
- Choose your .xlsb files. One or many at once. Each file is checked first: password-encrypted or damaged files are flagged straight away.
- Pick the output. With several files, get a ZIP with one .xlsx per file or a single workbook that holds every sheet.
- Click Convert to XLSX. Sheets, values, formulas, number formats, merged cells, column widths, comments and defined names are copied into a standard .xlsx.
- Download and check the short report under each file: it lists sheets, rows and formulas, and warns you if the file had macros, charts or images that are not carried over.
Private by design: nothing is uploaded
.xlsb is the format people pick for big, heavy workbooks: financial models, data exports, reports with hundreds of thousands of rows. Those are exactly the files you should not upload to an unknown converter. Here the conversion runs in your browser, in a background worker on your device. The page only downloads its own code and the SheetJS library from this site; you can confirm it in the Network tab or by going offline after the page loads.
What is an .xlsb file?
XLSB is the Excel Binary Workbook, introduced with Excel 2007 alongside .xlsx. The package is the same kind of ZIP file, but instead of XML each part is stored as compact binary records (the BIFF12 format). That makes large workbooks open and save faster and take less space, and it supports the same grid as .xlsx: 1,048,576 rows by 16,384 columns.
Unlike .xlsx, an .xlsb can contain VBA macros, and nothing in the extension tells you whether it does. Excel 2007 and later, on Windows and Mac, open it natively.
Why convert XLSB to XLSX
- Tools that only read .xlsxPython’s openpyxl, many import forms, CRMs and online services accept .xlsx but reject .xlsb.
- Share without macrosAn .xlsx cannot carry macros, so the person who receives it does not have to trust hidden code.
- Readable structure.xlsx is plain XML inside a ZIP: easy to inspect, compare, process with scripts or keep in version control.
- Batch clean-upConvert a folder of exports from a system that saves .xlsb in one go.
What is kept and what is not
We tested the converter with .xlsb files saved by Microsoft Excel, then opened the results in Excel.
Kept
- All sheets with their names and order, including hidden sheets
- Values, dates and text in any language
- Formulas, such as
=SUM(D2:D4), with their last result
- Number formats, merged cells, column widths and row heights
- Comments, hyperlinks and defined names
Not kept
- Macros (VBA): the .xlsx has none. The converter warns you when a file contained them
- Fonts, colours, fills, borders and alignment
- Conditional formatting and data validation
- Charts, images and shapes; pivot tables become their current values
- Freeze panes, print setup, sheet protection and anything else not listed as kept
If the macros matter, keep the .xlsb or open it in Excel and use Save As › Excel Macro-Enabled Workbook (.xlsm). If the formatting matters, Save As › Excel Workbook (.xlsx) in Excel keeps it.
XLSB vs XLSX: size and speed
For a workbook with a few thousand rows the difference is small. With hundreds of thousands of rows, .xlsb usually opens and saves noticeably faster in Excel and is somewhat smaller, because Excel does not have to parse XML. The .xlsx you get here is fully compressed; if it comes out too large, our Excel size reducer can help.
Password-protected .xlsb files
An .xlsb with a password to open is encrypted and cannot be read without it. If you know the password, remove it first with Remove Excel password, which handles .xlsb too, and then convert the result here. Nothing on this site tries to guess passwords.
Known limitations
- There is no file size limit or quota, but the whole workbook is converted in memory. Very large .xlsb files can need several times their size in RAM; on phones, keep files under about 20 MB.
- Data connections, Power Query queries and the data model are not converted.