What a Markdown file is and why you might have one
A markdown file is a plain text document with a .md extension — like readme.md or notes.md. It contains text with simple formatting symbols (asterisks for bold, hyphens for lists) that make it readable as plain text but can also be converted into formatted documents like web pages or PDFs.
You might have a markdown file because you downloaded it from a GitHub project, received it from a colleague, or created one yourself. The file looks like regular text with some extra symbols, and you can open it with almost any program on your computer.
The confusion usually comes from the .md extension itself — people assume it requires special software, when in reality any text editor will work. The formatting symbols are optional to understand; you can read the file as plain text without interpreting them at all.
Key Takeaways
- Markdown files are plain text documents with a .md extension that open in any text editor, including Notepad on Windows or TextEdit on Mac.
- The formatting symbols in markdown (asterisks, hyphens, brackets) are optional to understand — the file is readable as plain text whether you interpret them or not.
- If you want to see the formatted version with bold text, lists, and links displayed properly, use a markdown viewer or editor like Visual Studio Code, Typora, or an online markdown preview tool.
- Right-clicking the file and choosing "Open with" lets you pick which program to use, and you can set a default program so markdown files always open the same way.
Opening a markdown file with your default text editor
The simplest way to open a markdown file is to double-click it. On Windows, it will open in Notepad. On Mac, it will open in TextEdit. On Linux, it will open in your system's default text editor. The file displays as plain text with all the formatting symbols visible — you will see asterisks around bold words and hyphens before list items, but the text is completely readable.
This method works instantly and requires no installation. If you only need to read the file's content and do not care about seeing formatted text, this is the fastest route. The file opens in seconds and you can search, copy, and read normally.
Opening a markdown file on Windows
On Windows, double-clicking a markdown file opens it in Notepad by default. If you want to use a different program, right-click the file, select "Open with", and choose from the list. If your preferred program is not listed, click "Choose another app" and browse your computer.
To set a permanent default, right-click the file, select "Open with", choose your program, and check the box that says "Always use this app to open .md files". After that, all markdown files will open in your chosen program when you double-click them.
If you want to see the formatted version with bold text and proper list styling, install Visual Studio Code (free) or Notepad++ (free). Both are text editors that understand markdown and display the formatting symbols in a way that makes the structure clear, even if they do not show the final formatted appearance.
Opening a markdown file on Mac
On Mac, double-clicking a markdown file opens it in TextEdit. The file displays as plain text with all formatting symbols visible. If TextEdit is not your preference, right-click the file, select "Open With", and choose a different program from the list.
To set a permanent default, right-click the file, select "Open With", choose your program, and click "Change All". All markdown files will then open in that program by default.
For a better markdown experience on Mac, consider installing Visual Studio Code (free) or Typora (paid). Both programs understand markdown syntax and make the formatting symbols easier to read and work with. Typora in particular shows a preview of how the formatted text will look while you read or edit.
Using an online markdown viewer if you do not want to install anything
If you do not want to install new software, you can view a markdown file in your web browser using an online markdown viewer. Open your browser, go to a site like Markdown Live Preview (markdownlivepreview.com) or Dillinger (dillinger.io), and paste the contents of your markdown file into the text box. The formatted version appears on the right side of the screen.
This method works on any computer with internet access and requires no installation. The downside is that you have to copy and paste the file contents manually each time, and you cannot edit and save changes easily. This approach is best for one-time viewing or when you are on a computer where you cannot install programs.
Understanding markdown formatting symbols
Markdown uses simple symbols to mark formatting. A single asterisk or underscore on each side of a word makes it italic: *italic* or _italic_. Two asterisks or underscores make it bold: **bold** or __bold__. A hash symbol at the start of a line makes a heading: # Heading 1, ## Heading 2, and so on.
A hyphen, plus sign, or asterisk at the start of a line creates a bullet point. A number followed by a period creates a numbered list: 1. First item, 2. Second item. Square brackets with parentheses create links: [link text](url). You do not need to memorize these — they are just symbols that tell a markdown viewer how to format the text.
When you open a markdown file in a plain text editor like Notepad, you see all these symbols. When you open it in a markdown viewer or a program like Visual Studio Code, the symbols are hidden and the text appears formatted. Both views show you the same information; the symbols are just invisible in one version.
Choosing the right program for your needs
If you only read markdown files occasionally and do not care about seeing formatted text, use your default text editor (Notepad, TextEdit, or your system default). It is already on your computer and requires no setup.
If you read markdown files regularly or want to see the formatting, install Visual Studio Code. It is free, works on Windows, Mac, and Linux, and shows markdown in a clear, readable way. It also handles many other file types, so it is useful beyond just markdown.
If you want the most polished experience and do not mind paying, Typora (Mac and Windows) shows a live preview of formatted text as you read or edit. It is the closest thing to opening a finished document rather than a text file with symbols.
For quick one-time viewing without installation, use an online markdown viewer in your browser. Paste the file contents and see the formatted version instantly.
Frequently Asked Questions
Can I edit a markdown file and save my changes?
Yes. Any text editor lets you edit a markdown file and save it. Open the file, make your changes, and press Ctrl+S (Windows) or Command+S (Mac) to save. The file stays as a .md file with the same name unless you rename it.
What if the file has a different extension like .markdown or .mdown?
These are all markdown files with different extensions. Open them the same way — double-click to open in your default text editor, or right-click and choose "Open with" to pick a different program. The content and formatting symbols work identically.
Do I need internet to open a markdown file?
No. You can open a markdown file in any text editor on your computer without internet. You only need internet if you use an online markdown viewer in your browser.
Why does my markdown file look messy with all the symbols showing?
You are viewing it in a plain text editor like Notepad, which shows the raw formatting symbols. Install Visual Studio Code or use an online markdown viewer to see the formatted version with symbols hidden and text properly styled.
Can I convert a markdown file to a Word document or PDF?
Yes, but that requires additional software or an online converter. Visual Studio Code has extensions that can do this, and online tools like Pandoc (pandoc.org) can convert markdown to many formats. For most purposes, reading the markdown file as-is or viewing it in a markdown viewer is simpler.