Fuse.js

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.

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.

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 and results as Fuse — just async. Function-valued options (sortFn, getFn, keys[].getFn) aren't supported because functions can't be transferred to a worker; everything else carries over. See the Web Workers docs for the interactive demo and full API.

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>

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', ... }, ... }]

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' } }]

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 }
  ]
})

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

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
• AND or OR — tokenMatch: 'all' returns only records matching every word (filtering); the default 'any' matches any word
• Custom tokenizer — pass a regex or function via tokenize for tokens with internal punctuation (node.js, c++), or use Intl.Segmenter for CJK / Thai word segmentation. Unicode-aware by default

Available in the full build. See the Token Search docs for details and performance benchmarks.

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

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

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]]

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]] }

Fuse.match() does not support useTokenSearch — token search requires corpus-level statistics (df, fieldCount) that a one-off string comparison can't provide. Passing useTokenSearch: true throws an explicit error. Use new Fuse(docs, { useTokenSearch: true }).search(query) for token-search behavior.

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')

Fuse.js ships in two variants:

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

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

• fuse-swift: Swift port for iOS, macOS, tvOS, watchOS, visionOS, and Linux. Byte-equivalent results, idiomatic Swift API, syncs with each upstream release. Currently in 2.0.0-rc.1.

• Become a backer or sponsor on GitHub
• Become a backer or sponsor on Patreon
• One-time donation via PayPal

See DEVELOPERS.md for setup, scripts, and project structure.

See CONTRIBUTING.md for guidelines on issues and pull requests.