# Calculate the sum of numbers

Add numbers from left to right.

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

## Implementation

```javascript
function sumOf(values) { return values.reduce((a, b) => a + b); }
```

## Input

```json
[
  5,
  5,
  2
]
```

## Expected output

```json
12
```

## Edge case

Input:
```json
[
  0.1,
  0.2
]
```
Output:
```json
0.30000000000000004
```

## Limits

- Example: recipients per request — each recipient is one quota unit on Oveyon’s /v1/send.
- Floating-point sums are approximate, as the edge case shows.

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/calculate-the-sum-of-arguments.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: Takes one array instead of rest arguments. Original MDX retained as inert source evidence.