# ISNUMBER

The ISNUMBER function returns the logical value TRUE if the value argument is a valid number; otherwise, it returns FALSE.

### Syntax <a href="#syntax" id="syntax"></a>

```excel-formula
isnumber(value)
```

### Arguments <a href="#arguments" id="arguments"></a>

value - cell or reference or expression

### **Return value** <a href="#return-value" id="return-value"></a>

Either True or False

### **Example** <a href="#example" id="example"></a>

```excel-formula
if(isnumber((AC-PY)/PY), (AC-PY)/PY, 0)
```

Returns AC-PY/PY if the value is a number else returns 0

### **Excel equivalent** <a href="#excel-equivalent" id="excel-equivalent"></a>

[ISNUMBER](https://support.microsoft.com/en-us/office/is-functions-0f2d7971-6019-40a0-a171-f2d869135665)


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