🔍Regex Recipes

Extract Content Inside Parentheses

Extract text inside parentheses with nested limitation notes.

Pattern

\(([^)]*)\)

Explanation

Captures text within parentheses. Note: Does not handle nested parentheses reliably.

Examples

Simple

Input

Function(argument)

Output

Captures: argument

Multiple

Input

foo(bar) and baz(qux)

Output

Captures: bar, qux

Nested limitation

Input

outer(inner())

Output

Captures: inner( [incomplete]

Empty

Input

Empty()

Output

Captures: (empty)

Code Examples

JavaScript

const text = 'calculate(10) and format(result)';
const matches = [...text.matchAll(/\(([^)]*)\)/g)];
const contents = matches.map(m => m[1]);
// Result: ['10', 'result']

// For nested parentheses, use a parser or recursive regex
function extractWithNesting(text) {
  const stack = [];
  let current = '';
  let depth = 0;
  
  for (const char of text) {
    if (char === '(') {
      if (depth > 0) current += char;
      depth++;
    } else if (char === ')') {
      depth--;
      if (depth === 0) {
        stack.push(current);
        current = '';
      } else {
        current += char;
      }
    } else if (depth > 0) {
      current += char;
    }
  }
  return stack;
}

Try it Now

Open in Regex Tester

💡 Tips

Use [^)] to match anything except closing paren
For nested content, consider recursive regex (PCRE) or parser
Balance checking requires additional logic
Test with your actual use case data

⚠️ Common Pitfalls

Cannot reliably handle nested parentheses
Breaks with unbalanced parentheses
For complex nesting, use a proper parser
May need different approach for programming languages