applicationvndmsexcel

application/vnd.ms-excel is the internet media type (MIME type) used to denote Microsoft Excel spreadsheet files. It is used by web servers, email systems, and software to identify the file format and determine how to handle the content.

Historically, this MIME type is associated with the binary Excel format used by Excel 97-2003 and the .xls extension. With the introduction of Office Open XML, Excel now often uses other MIME types such as application/vnd.openxmlformats-officedocument.spreadsheetml.sheet for .xlsx. However, some servers and applications still label older Excel files as application/vnd.ms-excel. Related variants exist for macro-enabled workbooks and templates, reflecting different file structures and features.

In practice, the MIME type informs clients and servers about how to process the file, influencing whether an application should open the document or offer it for download. It is commonly delivered via HTTP Content-Type headers or used in email attachments to identify Excel data and select an appropriate handler.

Common extensions associated with this type include .xls for legacy binary files and .xlsx for OpenXML documents, with macro-enabled variants such as .xlsm and templates in related formats. The exact mapping can vary by software and platform, and some systems may use alternative or nested MIME types for the same underlying file content.

Security considerations apply to Excel files regardless of MIME type. Macros embedded in certain Excel formats can execute code, posing potential risks. Users should obtain files from trusted sources, be cautious with macros, and employ appropriate security settings when opening attachments.