console.warn()
Outputs a warning message to the console.
Syntax
console.warn(...data)
Returns
undefined — Returns `undefined`.
Examples
console.warn("Deprecated API used");
Output
Deprecated API used
console.warn("Retry %d of %d", 2, 3);
Output
Retry 2 of 3
Notes
- Typically rendered in yellow with a warning icon in browsers.
- Writes to stderr in Node.js.
- Supports printf-style format specifiers.
Browser & runtime support
| Environment | Since version |
|---|---|
| chrome | 1.0 |
| firefox | 1.0 |
| safari | 1.0 |
| edge | 12 |
| node | 0.10 |