XLTX Document — A .xltx file is a XLTX Document. It is a document format used for word processing, spreadsheets, presentations or ebooks.
Quick facts
What is .xltx
A .xltx file is a XLTX Document. It is a document format used for word processing, spreadsheets, presentations or ebooks.
In the mime-db registry it maps to application/vnd.openxmlformats-officedocument.spreadsheetml.template. When serving .xltx over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to application/vnd.openxmlformats-officedocument.spreadsheetml.template — and is delivered over HTTP via the Content-Type header.
How to open .xltx files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.template
Common software that reads/writes .xltx:
Relation chain
Related extensions
Related MIME types
Common uses
How to edit .xltx files
How to create .xltx files
Frequently asked questions
Common options include Microsoft 365, LibreOffice, Adobe Acrobat. You can also open many of these files with built-in viewers or a browser.
Create a new file in any text editor or the app that owns the format and save it with the .xltx extension.
application/vnd.openxmlformats-officedocument.spreadsheetml.template is the media type identifier used for .xltx files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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