fastest-levenshtein 🚀

Fastest JavaScript implementation of the Levenshtein distance algorithm - (up to 10x+ faster than closest competitor). This algorithm can be used to measure the similarity of two strings.

Note: if you need to take the edit distance of one string against many strings (maybe billions), I have created a GPU-implementation that will be atleast 1000x faster than this. Contact me, if you’re interested.

Build Status Coverage Status

$ npm i fastest-levenshtein

Usage

const {distance, closest} = require('fastest-levenshtein')

// Print levenshtein-distance between 'fast' and 'faster' 
console.log(distance('fast', 'faster'))
//=> 2

// Print string from array with lowest edit-distance to 'fast'
console.log(closest('fast', ['slow', 'faster', 'fastest']))
//=> 'faster'

Benchmark

I generated 500 pairs of strings with length N. I measured the ops/sec each library achieves to process all the given pairs. Higher is better. fastest-levenshtein is a lot faster in all cases.

Test Target N=4 N=8 N=16 N=32 N=64 N=128 N=256 N=512 N=1024
fastest-levenshtein 44423 23702 10764 4595 1049 291.5 86.64 22.24 5.473
js-levenshtein 21261 10030 2939 824 223 57.62 14.77 3.717 0.934
leven 19688 6884 1606 436 117 30.34 7.604 1.929 0.478
fast-levenshtein 18577 6112 1265 345 89.41 22.70 5.676 1.428 0.348
levenshtein-edit-distance 22968 7445 1493 409 109 28.07 7.095 1.789 0.445

Relative Performance

This image shows the relative performance between fastest-levenshtein and js-levenshtein (the 2nd fastest). fastest-levenshtein is always a lot faster. x-axis shows “times faster”.

Benchmark

License

This project is licensed under the MIT License - see the LICENSE.md file for details