Web’s fastest and most memory-flexible full-text search library with zero dependencies.
When it comes to raw search speed FlexSearch outperforms every single searching library out there and also provides flexible search capabilities like multi-word matching, phonetic transformations or partial matching. Depending on the used options it also provides the most memory-efficient index. Keep in mind that updating and/or removing existing items from the index has a significant cost. When your index needs to be updated very often then BulkSearch may be a better choice. FlexSearch also provides you a non-blocking asynchronous processing model as well as web workers to perform any updates or queries on the index in parallel through dedicated balanced threads.
FlexSearch Server is also available here: https://github.com/nextapps-de/flexsearch-server.
Installation Guide • API Reference • Presets • Custom Builds • Flexsearch Server • Changelog
Supported Platforms:
- Browser
- Node.js
Demos:
Library Comparison:
Get Latest (Stable Release):
| Build | File | CDN |
| flexsearch.min.js | Download | https://cdn.jsdelivr.net/gh/nextapps-de/flexsearch@master/dist/flexsearch.min.js |
| flexsearch.light.js | Download | https://cdn.jsdelivr.net/gh/nextapps-de/flexsearch@master/dist/flexsearch.light.js |
| flexsearch.compact.js | Download | https://cdn.jsdelivr.net/gh/nextapps-de/flexsearch@master/dist/flexsearch.compact.js |
| flexsearch.custom.js | Custom Build |
All Features:
| Feature | flexsearch.min.js | flexsearch.compact.js | flexsearch.light.js |
| Presets | ✔ | ✔ | – |
| Async Search | ✔ | ✔ | – |
| Web-Worker Sharding (not available in Node.js) | ✔ | – | – |
| Contextual Indexes | ✔ | ✔ | ✔ |
| Index Documents (Field-Search) | ✔ | ✔ | – |
| Partial Matching | ✔ | ✔ | ✔ |
| Multi-Phrase Search | ✔ | ✔ | ✔ |
| Relevance-based Scoring | ✔ | ✔ | ✔ |
| Auto-Balanced Cache by Popularity | ✔ | – | – |
| Suggestions (Results) | ✔ | – | – |
| Phonetic Matching | ✔ | ✔ | – |
| Customizable: Matcher, Encoder, Tokenizer, Stemmer, Filter | ✔ | ✔ | ✔ |
| File Size (gzip) | 5.0 kb | 3.9 kb | 2.7 kb |
It is also pretty simple to make Custom Builds
Benchmark Ranking
Comparison: Benchmark “Gulliver’s Travels”
Query Test: “Gulliver’s Travels”
| Rank | Library Name | Library Version | Single Phrase (op/s) | Multi Phrase (op/s) | Not Found (op/s) |
| 1 | FlexSearch *** | 0.3.6 | 363757 | 182603 | 1627219 |
| 2 | Wade | 0.3.3 | 899 | 6098 | 214286 |
| 3 | JS Search | 1.4.2 | 735 | 8889 | 800000 |
| 4 | JSii | 1.0 | 551 | 9970 | 75000 |
| 5 | Lunr.js | 2.3.5 | 355 | 1051 | 25000 |
| 6 | Elasticlunr.js | 0.9.6 | 327 | 781 | 6667 |
| 7 | BulkSearch | 0.1.3 | 265 | 535 | 2778 |
| 8 | bm25 | 0.2 | 71 | 116 | 2065 |
| 9 | Fuse | 3.3.0 | 0.5 | 0.4 | 0.7 |
Memory Test: “Gulliver’s Travels”
| Rank | Library Name | Library Version | Index Size * | Memory Allocation ** |
| 1 | FlexSearch **** | 0.3.1 | 1.33 Mb | 20.31 kb |
| 2 | Wade | 0.3.3 | 3.18 Mb | 68.53 kb |
| 3 | Fuse | 3.3.0 | 0.22 Mb | 156.46 kb |
| 4 | JSii | 1.0 | 8.9 Mb | 81.03 kb |
| 5 | bm25 | 0.2 | 6.95 Mb | 137.88 kb |
| 6 | BulkSearch | 0.1.3 | 1.53 Mb | 984.30 kb |
| 7 | Elasticlunr.js | 0.9.6 | 11.83 Mb | 68.69 kb |
| 8 | Lunr.js | 2.3.5 | 16.24 Mb | 84.73 kb |
| 9 | JS Search | 1.4.2 | 36.9 Mb | 53.0 kb |
* Index Size: The size of memory the index requires
** Memory Allocation: The amount of memory which was additionally allocated during a row of 10 queries
*** The preset “fastest” was used for this test
**** The preset “memory” was used for this test
Library Comparison: Benchmark “Gulliver’s Travels”