# Get the unique values of an array

Keep the first occurrence of each value with a Set.

Canonical: https://1loc.dev/array/get-the-unique-values-of-an-array/
Version: 1.0.0
Runtime: JavaScript · Node.js 22 / modern browsers
Verification: Local fixtures; no external services
Updated: 2026-10-28

## Implementation

```javascript
function uniqueValues(values) { return [...new Set(values)]; }
```

## Input

```json
[
  "delivered",
  "deferred",
  "delivered"
]
```

## Expected output

```json
[
  "delivered",
  "deferred"
]
```

## Edge case

Input:
```json
[
  null,
  null,
  0
]
```
Output:
```json
[
  null,
  0
]
```

## Limits

- Same idea as Remove duplicate values; SameValueZero treats NaN as equal to NaN.

The lab validates types and size before calling this function. Add equivalent validation at your own trust boundary.

## Source and license

Original: https://github.com/phuocng/1loc/blob/14b481cf60dff1620ab1bb99a43b1f68068cdd9b/contents/get-the-unique-values-of-an-array.mdx
Author: Nguyen Huu Phuoc and original contributors
Contributors: vreymond
Source commit: 14b481cf60dff1620ab1bb99a43b1f68068cdd9b
Copyright (c) 2020 phuoc-ng
License: MIT — https://1loc.dev/licenses/
Maintainer: Oveyon
Modifications: Keeps the Set variant. Original MDX retained as inert source evidence.