MD010 - Use spaces instead of tabs¶

Aliases: no-hard-tabs

What this rule does¶

Replaces tab characters with spaces to ensure consistent indentation across all editors and platforms.

Why this matters¶

Consistency: Tabs display differently in different editors (2, 4, or 8 spaces wide)
Team collaboration: Mixed tabs and spaces create confusing indentation and merge conflicts
Tool compatibility: Many Markdown tools and platforms expect spaces for proper formatting
Readability: Consistent spacing makes documents easier to read and maintain

Examples¶

✅ Correct¶

* Shopping list
    * Fruits
        * Apples
        * Bananas
    * Vegetables
        * Carrots
        * Broccoli

    Remember to check for freshness!

❌ Incorrect¶

→ represents a hard tab character.

* Shopping list
→* Fruits
→→* Apples
→→* Bananas
→* Vegetables
→→* Carrots
→→* Broccoli

→Remember to check for freshness!

🔧 Fixed¶

* Shopping list
    * Fruits
        * Apples
        * Bananas
    * Vegetables
        * Carrots
        * Broccoli

    Remember to check for freshness!

Configuration¶

[MD010]
spaces-per-tab = 4  # Number of spaces to replace each tab with (default: 4)

Configuration options explained¶

spaces-per-tab: How many spaces to use when replacing each tab character

Automatic fixes¶

This rule automatically replaces each tab character with the configured number of spaces (default: 4). This ensures your document looks the same in every editor.

Learn more¶

CommonMark specification - Technical details about tab handling

MD009 - Remove trailing spaces
MD007 - Keep list indentation consistent
MD005 - Keep list indentation consistent