For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt, and this page is available as Markdown at /reference/array/head.md.
Install massaman

    head es-toolkit

    Returns the first element of an array.

    const firstElement = head(arr);

    Usage

    head(arr)

    Use head when you want to get the first element of an array. If the array is empty, it returns undefined. This is useful when accessing data at the beginning of an array.

    import { head } from 'es-toolkit/array';

// Get the first element of a number array
const numbers = [1, 2, 3, 4, 5];
head(numbers);
// Returns: 1

// Get the first element of a string array
const strings = ['a', 'b', 'c'];
head(strings);
// Returns: 'a'

// Empty array returns undefined
const emptyArray: number[] = [];
head(emptyArray);
// Returns: undefined

    Type handling is safe.

    import { head } from 'es-toolkit/array';

// For non-empty arrays, the type is certain
const nonEmptyArray = [1, 2, 3] as const;
head(nonEmptyArray);
// Returns: 1 (type: 1)

// For regular arrays, undefined is possible
const maybeEmptyArray = [1, 2, 3];
head(maybeEmptyArray);
// Returns: 1 | undefined (type: number | undefined)

    Parameters

    arrreadonly T[]required

    The array from which to get the first element.

    Returns

    The first element of the array. Returns undefined if the array is empty.

    T | undefined
    Source: es-toolkit

    Re-exported verbatim from es-toolkit. Implementation, edge cases, and performance behavior are owned upstream. This page mirrors the documentation at the pinned version; the linked source is authoritative.