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# INDEXOF
Returns the index of the first occurrence of a specified number in an array.
The **INDEXOF** function returns the index of the first occurrence of a specified number within an array of numbers. It accepts numeric values or node references as arguments. If the value is not found in the input array, the function returns 0.
### Syntax
```javascript
INDEXOF(list, value)
```
### Arguments
list - The input array of numbers to be checked (Required).
value - The number to be searched for in the list (Required).
### Example
```javascript
INDEXOF([LIST],VALUE)
```
In the example below, the **INDEXOF** function is used to check whether the *Revenue* in any quarter is equal to the *Sales for Q1*.
Applying INDEXOF function
---
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