Fix "Invalid control character" JSON Error

The "Invalid control character" error occurs when JSON contains unescaped control characters like newlines, tabs, or other special characters that must be escaped in JSON strings.

Control characters (newlines \n, tabs \t, etc.) must be properly escaped in JSON. Learn how to fix this instantly using our free JSON Fixer tool.

What Are Control Characters?

Control characters are special characters that control text formatting:

• \n - Newline
• \t - Tab
• \r - Carriage return
• \b - Backspace
• \f - Form feed

Broken JSON Example

{
  "message": "Line 1
Line 2"  ← Unescaped newline
}

{
  "message": "Line 1\nLine 2"
}