# every method

The `every` method checks array elements according to a passed function. The method returns `true` if the passed function returns `true` for all array elements, otherwise the method returns `false`.

You can pass three parameters to the function. If these parameters are present (they are not required), then the first one will automatically get the array element, the second one will get its number in the array (index), and the third one will get the array itself.

## Syntax

`array.every(function(element, index, array) { return true or false; });`

## Example

We check that all elements in an array of numbers are positive:

`let arr = [1, 2, 3, 4, 5]; let check = arr.every(function(elem) { if (elem >= 0) { return true; } else { return false; } }); console.log(check);`

The code execution result:

`true`

## Example

Let's check that the product of an element and its index is always less than `30`:

`let arr = [1, 2, 3, 4, 5]; let check = arr.every(function(elem, index) { if (elem * index < 30) { return true; } else { return false; } }); console.log(check);`

The code execution result:

`true`

## Example

If necessary, an array itself can be passed to the third parameter:

`let check = arr.every(function(elem, index, arr) { array arr will be available here });`

## See also

- the `some` method
  that also allows you to perform an array check
- the `map` and `forEach` methods
  that allow you to apply a function to each element of an array
- the `reduce` and `reduceRight` methods
  that reduce an array to a single value

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