# web-audio-beat-detector

> A beat detection utility which is using the Web Audio API.

Latest version **8.2.39** (published 2026-08-26) · MIT license · 0 weekly downloads

## Install

```sh
npm install web-audio-beat-detector
pnpm add web-audio-beat-detector
yarn add web-audio-beat-detector
bun add web-audio-beat-detector
```

## Health

**Score 70/100 (B)** — status: active.

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

Warnings: low downloads.

## Facts

| | |
|---|---|
| Version | 8.2.39 |
| Published | 2026-08-26 |
| First published | 2016-06-16 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Dependencies | 4 |
| Unpacked size | 41.3 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 679 |
| Author | Christoph Guttandin |
| Maintainers | chrisguttandin |

## Links

- npm: https://www.npmjs.com/package/web-audio-beat-detector
- Repository: https://github.com/chrisguttandin/web-audio-beat-detector
- Issues: https://github.com/chrisguttandin/web-audio-beat-detector/issues
- npm.io page: https://npm.io/package/web-audio-beat-detector

## Dependencies (4)

- [tslib](https://npm.io/package/tslib.md) ^2.8.1
- [@babel/runtime](https://npm.io/package/@babel/runtime.md) ^7.29.7
- [web-audio-beat-detector-broker](https://npm.io/package/web-audio-beat-detector-broker.md) ^5.0.16
- [web-audio-beat-detector-worker](https://npm.io/package/web-audio-beat-detector-worker.md) ^6.0.14

## Recent versions

- 8.2.39 (latest) — 2026-08-26
- 8.2.38 — 2026-07-29
- 8.2.37 — 2026-06-20
- 8.2.36 — 2026-03-19
- 8.2.35 — 2026-02-06
- 8.2.34 — 2026-01-17
- 8.2.33 — 2026-01-09
- 8.2.32 — 2025-12-20
- 8.2.31 — 2025-09-29
- 8.2.30 — 2025-07-17
- 8.2.29 — 2025-06-12
- 8.2.28 — 2025-05-16
- 8.2.27 — 2025-03-26
- 8.2.26 — 2025-03-24
- 8.2.25 — 2025-03-13
- … 380 more at https://npm.io/package/web-audio-beat-detector/versions

## README

![logo](https://repository-images.githubusercontent.com/61281324/6526e580-3b28-11ea-90ce-be241599f494)

# web-audio-beat-detector

**A beat detection utility which is using the Web Audio API.**

[![version](https://img.shields.io/npm/v/web-audio-beat-detector.svg?style=flat-square)](https://www.npmjs.com/package/web-audio-beat-detector)

This module is based on the technique explained by [Joe Sullivan](http://joesul.li/van/) in his article [Beat Detection Using JavaScript and the Web Audio API](http://joesul.li/van/beat-detection-using-web-audio/). It retrieves the beats as BPM of a given AudioBuffer. The algorithm used is not as complex (and expensive to compute) as many others. But it yields surprisingly good results especially for electronic music.

## Usage

The `web-audio-beat-detector` module is available on
[npm](https://www.npmjs.com/package/web-audio-beat-detector) and can be installed as usual.

```shell
npm install web-audio-beat-detector
```

You can then import its public function `analyze()` like this:

```js
import { analyze } from 'web-audio-beat-detector';
```

The `analyze()` function expects an `AudioBuffer` as its first parameter and it returns a `Promise`
which eventually resolves with the tempo of that buffer as a number. An example usage might look
like this:

```js
analyze(audioBuffer)
    .then((tempo) => {
        // the tempo could be analyzed
    })
    .catch((err) => {
        // something went wrong
    });
```

Additionally you can also import the `guess()` function like this:

```js
import { guess } from 'web-audio-beat-detector';
```

The `guess()` function expects an `AudioBuffer` as well and also returns a `Promise`. The `Promise`
will resolve with an object containing the estimated BPM (the rounded tempo) and the offset of the
first beat in seconds.

```js
guess(audioBuffer)
    .then(({ bpm, offset, tempo }) => {
        // the bpm and offset could be guessed
        // the tempo is the same as the one returned by analyze()
    })
    .catch((err) => {
        // something went wrong
    });
```

`analyze()` and `guess()` do both support `offset` and `duration` as optional arguments. When specified these two values are used to select only a part of the given `AudioBuffer`. There usage is the same as described in the documentation of the [`AudioBufferSourceNode.start()`](https://webaudio.github.io/web-audio-api/#widl-AudioBufferSourceNode-start-void-double-when-double-offset-double-duration) method.

By default the bpm are expected to be between 90 and 180 bpm. This can be changed by specifying the `tempoSettings`. These can be passed as the last argument to `analyze()` or `guess()`.

```js
// with an offset and duration
analyze(audioBuffer, 1, 10, { maxTempo: 120, minTempo: 60 });
// with no other arguments
analyze(audioBuffer, { maxTempo: 120, minTempo: 60 });
```

## Acknowledgement

A more comprehensive implementation has been done by [José M. Pérez](https://jmperezperez.com). It
comes with an UI to search for tracks on Spotify which can then be analyzed. He also wrote a blog
post
([Detecting tempo of a song using browser's Audio API](https://jmperezperez.com/bpm-detection-javascript/))
about it.

---
_Source: https://npm.io/package/web-audio-beat-detector · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._