What is brace expansion?

Brace expansion is a powerful pattern-matching feature found in Unix shells like Bash. It allows you to generate multiple strings from a single pattern by expanding sequences or lists enclosed in curly braces. For example, {1..5} expands to 1 2 3 4 5, and {a,b,c} expands to a b c. This feature is incredibly useful for quickly creating file names, running commands on multiple items, or generating test data without typing each item individually.

Tool description

This tool generates all possible expansions from brace patterns, similar to how Unix shells process brace expansion. Enter a pattern with curly braces, and the tool will instantly show you all the expanded values. It's perfect for testing brace patterns before using them in scripts or for quickly generating lists of values.

Features

  • Numeric ranges: Expand numeric sequences like {1..10} or {001..100} with zero-padding
  • Alphabetic ranges: Generate letter sequences like {a..z} or {A..Z}
  • List expansion: Expand comma-separated lists like {red,green,blue}
  • Complex patterns: Combine multiple braces like file-{a,b}-{1..3}.txt
  • Nested patterns: Support for nested brace expressions
  • Instant preview: See results in real-time as you type
  • Copy output: Easily copy the expanded list for use elsewhere

Use Cases

  • File name generation: Quickly create patterns for batch file operations like photo-{001..100}.jpg
  • Script testing: Test brace expansion patterns before using them in shell scripts
  • Batch operations: Generate lists of items for batch renaming, copying, or processing
  • URL generation: Create multiple URLs with sequential or varied patterns
  • Test data creation: Generate test cases or sample data sets with consistent naming
  • Command preparation: Preview the result of brace expansions in complex commands
  • Documentation: Demonstrate brace expansion patterns and their results