---
title: "isBad"
description: "Tests to see whether or not the given value's quality is bad."
---

# isBad

> Tests to see whether or not the given value's quality is bad.

**This function is used by Ignition's Expression language.**

## Description

Tests to see whether or not the given value's [quality](platform/tags/quality-codes-and-overlays/quality-codes-and-overlays.md) is bad.

## Syntax

`isBad(value)`

### Parameters

| Type   | Parameter | Description                                 |
|--------|-----------|---------------------------------------------|
| Object | `value`   | A value to check if its quality is bad.     |

### Returns

**Boolean** - Returns true if the value's quality is bad, or false if it is not.

## Examples

```py title="Code Snippet"
isBad({path/to/myTag}) //Returns True if the value's quality is bad, False otherwise.
```