# @turf/boolean-concave

> Takes a polygon and return true or false as to whether it is concave or not.

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

## Install

```sh
npm install @turf/boolean-concave
pnpm add @turf/boolean-concave
yarn add @turf/boolean-concave
bun add @turf/boolean-concave
```

## 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 | 2018-02-21 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Dependencies | 4 |
| Unpacked size | 11.9 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 10491 |
| Author | Turf Authors |
| Maintainers | rowanwins, tmcw, morganherlocker, tcql, mdfedderly, twelch, jamesmilneruk, morgan.herlocker |
| Keywords | turf, polygon, concave, convex, boolean |

## Links

- npm: https://www.npmjs.com/package/@turf/boolean-concave
- 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/boolean-concave

## Dependencies (4)

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

## 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
- … 16 more at https://npm.io/package/@turf/boolean-concave/versions

## README

# @turf/boolean-concave

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

## booleanConcave

Takes a polygon and return true or false as to whether it is concave or not.

### Parameters

*   `polygon` **[Feature][1]<[Polygon][2]>** to be evaluated

### Examples

```javascript
var convexPolygon = turf.polygon([[[0,0],[0,1],[1,1],[1,0],[0,0]]]);

turf.booleanConcave(convexPolygon)
//=false
```

Returns **[boolean][3]** true/false

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

[2]: https://tools.ietf.org/html/rfc7946#section-3.1.6

[3]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean

<!-- 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/boolean-concave
```

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/boolean-concave · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._