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/sampleSize.md.
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    sampleSize es-toolkit

    Returns a new array of randomly selected elements with the specified size.

    const sampled = sampleSize(array, size);

    Usage

    sampleSize(array, size)

    Use sampleSize when you want to randomly sample multiple elements from an array. It uses Floyd's algorithm to efficiently generate random samples without duplicates. It's useful for extracting samples in surveys or randomly selecting multiple items in games.

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

// Randomly select 3 from a number array.
const numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
const randomNumbers = sampleSize(numbers, 3);
// Returns: [2, 7, 9] (example, actually random)

// Randomly select 2 from a string array.
const fruits = ['apple', 'banana', 'cherry', 'date', 'elderberry'];
const randomFruits = sampleSize(fruits, 2);
// Returns: ['cherry', 'apple'] (example, actually random)

    You can sample with various sizes.

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

const items = ['a', 'b', 'c', 'd', 'e'];

// Select 1 element
const single = sampleSize(items, 1);
// Returns: ['c'] (example)

// Select same as entire array size (shuffle effect)
const all = sampleSize(items, 5);
// Returns: ['b', 'd', 'a', 'e', 'c'] (example)

// Select empty array
const none = sampleSize(items, 0);
// Returns: []

    Parameters

    arrayreadonly T[]required

    The array to sample from.

    sizenumberrequired

    The number of elements to select.

    Returns

    Returns a new array consisting of randomly selected elements.

    T[]

    Throws

    Throws an error if size is greater than the length of the array.

    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.