XLS
The legacy binary spreadsheet format used by Microsoft Excel before XLSX, storing worksheets, formulas, formatting, charts, and other workbook data in an OLE compound file.
General information
- Format name
- Microsoft Excel Binary File Format
- Extension
.xls- MIME type
application/vnd.ms-excel- Category
- document
- Data type
- Binary
- Developer
- Microsoft
File signatures
| Offset | Hexadecimal | ASCII | Description |
|---|---|---|---|
| 0 | D0 CF 11 E0 A1 B1 1A E1 | — | OLE Compound File signature shared by XLS and several other legacy Microsoft Office formats, so it is not unique to XLS. |
Common uses
Legacy spreadsheets
Financial workbooks
Data tables
Business reports
Archived Excel files
Related formats
Technical resources
| Resource | Publisher | Link |
|---|---|---|
| Excel Binary File Format (.xls) Structure | Microsoft | Open resource ↗ |
| Media Types Registry | IANA | Open resource ↗ |
Record information
- Verified
- October 4, 2026
- Last updated
- October 4, 2026