# Sum an array of numbers

Add numeric values with an explicit result for an empty array.

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

## Implementation

```javascript
function sum(values) { return values.reduce((total, value) => total + value, 0); }
```

## Input

```json
[
  4,
  8,
  3
]
```

## Expected output

```json
15
```

## Edge case

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

## Limits

- Floating-point arithmetic is approximate; use integer minor units or a decimal library for money.
- The lab bounds values to ±1 billion and arrays to 1,000 total items.

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-sum-of-an-array-of-numbers.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.