# @turf/length

> Calculates the length of a line, perfect for paths or routes.

Latest version **7.4.0** (published 2026-08-03) · MIT license · 0 weekly downloads

## Install

```sh
npm install @turf/length
pnpm add @turf/length
yarn add @turf/length
bun add @turf/length
```

## Health

**Score 80/100 (A)** — status: active.

Positive: has types; esm support; no vulnerabilities; has provenance; recently updated; high maintenance score; high quality score; popular repo.

Warnings: low downloads.

## Facts

| | |
|---|---|
| Version | 7.4.0 |
| Published | 2026-08-03 |
| First published | 2017-10-29 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Dependencies | 5 |
| Unpacked size | 11.2 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 10488 |
| Author | Turf Authors |
| Maintainers | rowanwins, tmcw, morganherlocker, tcql, mdfedderly, twelch, jamesmilneruk, morgan.herlocker |
| Keywords | turf, linestring, length, distance, units, gis |

## Links

- npm: https://www.npmjs.com/package/@turf/length
- Repository: https://github.com/Turfjs/turf
- Issues: https://github.com/Turfjs/turf/issues
- Funding: https://opencollective.com/turf
- npm.io page: https://npm.io/package/@turf/length

## Dependencies (5)

- [tslib](https://npm.io/package/tslib.md) ^2.8.1
- [@turf/meta](https://npm.io/package/@turf/meta.md) 7.4.0
- [@turf/helpers](https://npm.io/package/@turf/helpers.md) 7.4.0
- [@turf/distance](https://npm.io/package/@turf/distance.md) 7.4.0
- [@types/geojson](https://npm.io/package/@types/geojson.md) ^7946.0.10

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## Recent versions

- 7.4.0 (latest) — 2026-08-03
- 7.1.0-alpha.70 (prerelease) — 2024-08-09
- 7.3.5 — 2026-04-19
- 7.3.4 — 2026-02-08
- 7.3.3 — 2026-01-28
- 7.3.2 — 2026-01-14
- 7.3.1 — 2025-11-27
- 7.3.0 — 2025-11-17
- 7.2.0 — 2024-12-29
- 7.1.0 — 2024-08-09
- 7.1.0-alpha.7 — 2024-06-25
- 7.0.0 — 2024-06-07
- 7.0.0-alpha.116 — 2024-05-07
- 7.0.0-alpha.115 — 2024-04-23
- 7.0.0-alpha.114 — 2024-03-11
- … 21 more at https://npm.io/package/@turf/length/versions

## README

# @turf/length

<!-- Generated by documentation.js. Update this documentation by updating the source code. -->

## length

Takes a [GeoJSON][1] and measures its length in the specified units, [(Multi)Point][2]'s distance are ignored.

### Parameters

*   `geojson` **[Feature][3]<([LineString][4] | [MultiLineString][5])>** GeoJSON to measure
*   `options` **[Object][6]** Optional parameters (optional, default `{}`)

    *   `options.units` **Units** Supports all valid Turf [Units][7]. (optional, default `kilometers`)

### Examples

```javascript
var line = turf.lineString([[115, -32], [131, -22], [143, -25], [150, -34]]);
var length = turf.length(line, {units: 'miles'});

//addToMap
var addToMap = [line];
line.properties.distance = length;
```

Returns **[number][8]** length of GeoJSON

[1]: https://tools.ietf.org/html/rfc7946#section-3

[2]: https://tools.ietf.org/html/rfc7946#section-3.1.2

[3]: https://tools.ietf.org/html/rfc7946#section-3.2

[4]: https://tools.ietf.org/html/rfc7946#section-3.1.4

[5]: https://tools.ietf.org/html/rfc7946#section-3.1.5

[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object

[7]: https://turfjs.org/docs/api/types/Units

[8]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number

<!-- This file is automatically generated. Please don't edit it directly. If you find an error, edit the source file of the module in question (likely index.js or index.ts), and re-run "yarn docs" from the root of the turf project. -->

---

This module is part of the [Turfjs project](https://turfjs.org/), an open source module collection dedicated to geographic algorithms. It is maintained in the [Turfjs/turf](https://github.com/Turfjs/turf) repository, where you can create PRs and issues.

### Installation

Install this single module individually:

```sh
$ npm install @turf/length
```

Or install the all-encompassing @turf/turf module that includes all modules as functions:

```sh
$ npm install @turf/turf
```

---
_Source: https://npm.io/package/@turf/length · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._