Format Odyssey

FILE FORMAT GUIDE

ODT File: What It Is & How to Open It

An ODT file is an OpenDocument Text package. It combines document XML, styles, metadata and optional embedded resources in a ZIP-based package with a defined media type.

Quick facts

Extension
.odt
Format
OpenDocument Text
Category
document
MIME type
application/vnd.oasis.opendocument.text
Standard / developer
OASIS Open
Open with
LibreOffice Writer

What is ODT?

A conforming OpenDocument package places an uncompressed mimetype entry first and includes META-INF/manifest.xml. For ODT, the package media type is application/vnd.oasis.opendocument.text.

How to open ODT

LibreOffice WriterWindows / macOS / Linux

Open the .odt file in LibreOffice Writer. Save a copy before converting it if layout fidelity matters.

Opening and saving files — LibreOffice Help

Common uses and compatibility

  • Store an editable word-processing document using the OpenDocument standard

Things to check

  • A valid package structure does not guarantee identical layout or feature support in every office application.

Advanced inspection

These developer and command-line workflows inspect structure or metadata. They are not the default way most people open the file.

Python zipfileCommand-line tool and standard library

Run python -m zipfile -l document.odt to inspect package entries without rendering embedded content. Confirm that mimetype and META-INF/manifest.xml are present before using an office application.

Technical details

Signature
50 4B 03 04 at offset 0; mimetype at offset 30; application/vnd.oasis.opendocument.text at offset 38
Encoding
Not applicable
Container
OpenDocument ZIP package with META-INF/manifest.xml
Compression
The leading mimetype entry is stored without compression; other package entries may use ZIP compression

OpenDocument Version 1.3

Related formats

  • Portable Document Format

    PDF is commonly used as a fixed-layout final document, while ODT preserves an editable OpenDocument package.

  • XML Paper Specification Document

    XPS is a fixed-layout package; ODT stores editable text-document content and resources under OpenDocument rules.

  • EPUB Publication

    Both use ZIP-based packages with a leading mimetype entry, but EPUB targets publication reading systems and ODT targets office documents.

Sources & review

Sources reviewed 2026-09-19.