What is a .md file? (And how to open one on your phone)

Updated: 2026-10-29

A file ending in .md is a markdown file. Markdown is a way of writing formatted text using ordinary characters, so the file is just plain text that any device can store.

Here's a small example. This is what the file contains:

# Shopping list

Buy these **today**:

- Milk
- Bread
- [ ] Call the bakery

A markdown viewer turns it into a formatted page: a large "Shopping list" heading, the word "today" in bold, a bulleted list, and a checkbox you can tick.

Why so many files are .md now

• README files. Almost every software project has a README.md that explains what it is.
• Notes apps. Obsidian, Logseq, Joplin and many other apps store notes as .md files.
• AI assistants. ChatGPT, Claude and Gemini write their answers in markdown. When you save or export an answer, you often get a .md file.
• Documentation. Many manuals, wikis and course notes are written in markdown.

Markdown is popular because it's readable even without a viewer, works on every system, and is easy to convert to a web page or PDF.

What markdown can contain

• Headings (#, ##)
• Bold and italic text
• Bulleted, numbered and checkbox lists
• Links and images
• Tables
• Code blocks
• Often math formulas ($E = mc^2$) and diagrams (Mermaid)

The last two aren't part of basic markdown, so simple viewers show them as raw text. A good viewer renders them.

How to read a .md file on Android

Android can't format markdown on its own. Install a markdown viewer and open the file with it.

Get it on Google Play

MD Reader opens .md and .markdown files from Files, Downloads, Google Drive, email attachments and the share menu. It also renders tables, math and diagrams. The full steps are in how to open a .md file on Android.

Can I just rename it to .txt?

You can, and you'll be able to read the text. But you'll see all the symbols, tables will look like rows of | characters, and checkboxes won't work. Why your .md file shows # and ** symbols explains the difference.