Fuse.js

License

Fuse.js is a lightweight, zero-dependency fuzzy-search library written in TypeScript. It works in the browser and on the server, and is designed for searching small-to-medium datasets on the client side where you can't rely on a dedicated search backend.

✨ What's New: Token Search

Multi-word fuzzy search with relevance ranking. Type "javascrpt paterns" and find "JavaScript Patterns" — typo tolerance, multiple words, and smart ranking all at once.

const fuse = new Fuse(docs, {
  useTokenSearch: true,
  keys: ['title', 'author', 'description']
})

fuse.search('javascrpt paterns')
// → [{ item: { title: 'JavaScript Patterns', ... } }]

See Token Search below for details.

🧪 Beta: Web Workers

Search large datasets without freezing the UI. FuseWorker splits your data across multiple Web Workers and searches in parallel — ~5x faster on 100K documents.

import { FuseWorker } from 'fuse.js/worker'

const fuse = new FuseWorker(docs, {
  keys: ['title', 'author', 'description']
})

const results = await fuse.search('query')
fuse.terminate()

Same options, same results as Fuse — just async. See the Web Workers docs for the interactive demo and full API.

Installation

npm install fuse.js

yarn add fuse.js

Or include directly via CDN:

<script src="https://cdn.jsdelivr.net/npm/fuse.js/dist/fuse.min.mjs"></script>

Quick Start

import Fuse from 'fuse.js'

const books = [
  { title: "Old Man's War", author: 'John Scalzi' },
  { title: 'The Lock Artist', author: 'Steve Hamilton' },
  { title: 'HTML5', author: 'Remy Sharp' },
  { title: 'JavaScript: The Good Parts', author: 'Douglas Crockford' }
]

const fuse = new Fuse(books, {
  keys: ['title', 'author']
})

fuse.search('javscript')
// → [{ item: { title: 'JavaScript: The Good Parts', ... }, ... }]

Features

Fuzzy Search

The core of Fuse.js. Uses the Bitap algorithm for approximate string matching — handles typos, misspellings, and partial matches out of the box.

fuse.search('javscript')
// → [{ item: { title: 'JavaScript: The Good Parts', author: 'Douglas Crockford' } }]

Weighted Keys

Search across multiple fields with different importance levels. Title matches can rank higher than description matches.

const fuse = new Fuse(docs, {
  keys: [
    { name: 'title', weight: 2 },
    { name: 'description', weight: 1 }
  ]
})

Extended Search

Use operators for precise control: exact match (=), prefix (^), suffix (!), and more. Enable with useExtendedSearch: true.

const fuse = new Fuse(list, {
  useExtendedSearch: true,
  keys: ['title']
})

fuse.search('=exact match')   // exact match
fuse.search('^prefix')        // starts with
fuse.search('!term')          // does not include

Token Search

Splits multi-word queries into individual terms, fuzzy-matches each independently, and ranks results using BM25-style IDF weighting. Enable with useTokenSearch: true.

const fuse = new Fuse(docs, {
  useTokenSearch: true,
  keys: ['title', 'body']
})

fuse.search('express midleware rout')
// Finds "Express Middleware" and "Express Routing Guide" despite typos

Typo tolerance per word — each term is fuzzy-matched independently
Relevance ranking — rare terms are weighted higher than common ones
Word order independent — "patterns javascript" and "javascript patterns" return identical results
No query length limit — long multi-word queries work naturally since each term is searched separately

Available in the full build. See TOKEN_SEARCH.md for details and performance benchmarks.

Logical Search

Combine conditions with $and and $or for complex queries. Available in the full build.

fuse.search({
  $and: [
    { title: 'javascript' },
    { author: 'crockford' }
  ]
})

Match Highlighting

Get character-level match indices for highlighting search results in your UI.

const fuse = new Fuse(list, {
  includeMatches: true,
  keys: ['title']
})

const result = fuse.search('javscript')
// result[0].matches[0].indices → [[0, 9]]

Single String Matching

Use Fuse.match() to fuzzy-match a pattern against a single string without creating an index. Useful for one-off comparisons or custom filtering.

const result = Fuse.match('javscript', 'JavaScript: The Good Parts')
// → { isMatch: true, score: 0.04, indices: [[0, 9]] }

Dynamic Collections

Add and remove documents from a live index without rebuilding.

fuse.add({ title: 'New Book', author: 'New Author' })
fuse.remove((doc) => doc.title === 'Old Book')

Builds

Fuse.js ships in two variants:

Build	Includes	Min + gzip
Full	Fuzzy + Extended + Logical + Token search	~8 kB
Basic	Fuzzy search only	~6.5 kB

Use the basic build if you only need fuzzy search and want the smallest bundle size.

Documentation

For the full API reference, configuration options, scoring theory, and interactive demos, visit fusejs.io.