Format comparison
XLS vs RTF
How do XLS and RTFcompare? Here's everything you need to know to choose the right format — and how to convert between them.
.xls
Full guide →Microsoft Excel Spreadsheet (Legacy)
XLS is the legacy binary format used by Microsoft Excel before 2007. While superseded by XLSX, many existing spreadsheets and enterprise systems still use this format.
.rtf
Full guide →Rich Text Format
RTF is a cross-platform document format that supports basic formatting like bold, italic, fonts, and colors. It's a universal middle ground between plain text and full document formats.
| Specification | XLS | RTF |
|---|---|---|
| Full name | Microsoft Excel Spreadsheet (Legacy) | Rich Text Format |
| Extension | .xls | .rtf |
| MIME type | application/vnd.ms-excel | application/rtf |
| Category | Document | Document |
| Developer | Microsoft | Microsoft |
| Year introduced | 1987 | 1987 |
XLS advantages
- Compatible with older Excel versions
- Widely recognized format
- Supported by all major spreadsheet apps
- Large installed base
XLS limitations
- Limited to 65,536 rows and 256 columns
- Larger file sizes than XLSX
- Binary format — harder to recover
- Missing modern Excel features
RTF advantages
- Cross-platform compatibility
- Basic formatting support
- No macros — safer than DOC/DOCX
- Human-readable markup
RTF limitations
- Limited advanced formatting
- Larger than plain text
- No modern features like tables or charts
- Inconsistent rendering across editors
Which should you use?
XLS and RTF serve different purposes. XLS is ideal for legacy spreadsheet compatibility, while RTF excels at cross-platform document sharing.
Best uses for XLS
Legacy spreadsheet compatibility
Older enterprise systems
Historical data archives
Backward-compatible exports
Best uses for RTF
Cross-platform document sharing
Simple formatted documents
Email-safe document attachments
Clipboard data exchange
Convert between XLS and RTF
Need to switch formats? Convert for free with SquishConvert.