# Reverse a string

Reverse Unicode code points without splitting surrogate pairs.

Canonical: https://1loc.dev/string/reverse-a-string/
Version: 1.0.0
Runtime: JavaScript · Node.js 22 / modern browsers
Verification: Local fixtures; no external services
Updated: 2026-10-28

## Implementation

```javascript
function reverse(value) { return Array.from(value).reverse().join(''); }
```

## Input

```json
"code"
```

## Expected output

```json
"edoc"
```

## Edge case

Input:
```json
"A😀B"
```
Output:
```json
"B😀A"
```

## Limits

- Combining marks and joined emoji can still split: code points are not grapheme clusters.
- For user-facing text, segment graphemes with Intl.Segmenter before reversing.

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/reverse-a-string.mdx
Author: Nguyen Huu Phuoc and original contributors
Contributors: See original repository history
Source commit: 14b481cf60dff1620ab1bb99a43b1f68068cdd9b
Copyright (c) 2020 phuoc-ng
License: MIT — https://1loc.dev/licenses/
Maintainer: Oveyon
Modifications: Curated implementation; explicit input bounds, edge cases, local fixtures and rebuilt presentation. Original MDX retained as inert source evidence.