## isValidHostname() function [​](/content/docs/sdk/core.isvalidhostname#isvalidhostname-function "Direct link to isValidHostname(/index.html) function")

Tests whether a given input is a valid hostname.

__NOTE: Does not validate that the input is a valid domain name, only a valid hostname.__

**Signature:**

```typescript
export declare function isValidHostname(input: string): boolean;
```

## Parameters [​](/content/docs/sdk/core.isvalidhostname#parameters "Direct link to Parameters"/index.html)

| Parameter | Type | Description |
| --- | --- | --- |
| input | string | The input to test. |

**Returns:**

boolean

True if `input` is a valid hostname, otherwise returns false.

### Valid matches:
- foo
- foo.com
- foo.bar.com
- foo.org
- foo.bar.co.uk
- localhost
- LOCALHOST
- foo-bar-baz
- foo_bar
- foobar123

### Invalid matches:
- foo.com/bar
- [https://foo.com](https://foo.com/)
- foo_-bar_- 
- foo | rm -rf /

- [isValidHostname() function](/content/docs/sdk/core.isvalidhostname#isvalidhostname-function/index.html)
- [Parameters](/content/docs/sdk/core.isvalidhostname#parameters/index.html)