The fastest deep equal with ES6 Map, Set and Typed arrays support.

Build Status npm Coverage Status


npm install fast-deep-equal


  • ES5 compatible
  • works in node.js (8+) and browsers (IE9+)
  • checks equality of Date and RegExp objects by value.

ES6 equal (require('fast-deep-equal/es6')) also supports:

  • Maps
  • Sets
  • Typed arrays


var equal = require('fast-deep-equal');
console.log(equal({foo: 'bar'}, {foo: 'bar'})); // true

To support ES6 Maps, Sets and Typed arrays equality use:

var equal = require('fast-deep-equal/es6');
console.log(equal(Int16Array([1, 2]), Int16Array([1, 2]))); // true

To use with React (avoiding the traversal of React elements’ _owner property that contains circular references and is not needed when comparing the elements - borrowed from react-fast-compare):

var equal = require('fast-deep-equal/react');
var equal = require('fast-deep-equal/es6/react');

Performance benchmark

Node.js v12.6.0:

fast-deep-equal x 261,950 ops/sec ±0.52% (89 runs sampled)
fast-deep-equal/es6 x 212,991 ops/sec ±0.34% (92 runs sampled)
fast-equals x 230,957 ops/sec ±0.83% (85 runs sampled)
nano-equal x 187,995 ops/sec ±0.53% (88 runs sampled)
shallow-equal-fuzzy x 138,302 ops/sec ±0.49% (90 runs sampled)
underscore.isEqual x 74,423 ops/sec ±0.38% (89 runs sampled)
lodash.isEqual x 36,637 ops/sec ±0.72% (90 runs sampled)
deep-equal x 2,310 ops/sec ±0.37% (90 runs sampled)
deep-eql x 35,312 ops/sec ±0.67% (91 runs sampled)
ramda.equals x 12,054 ops/sec ±0.40% (91 runs sampled)
util.isDeepStrictEqual x 46,440 ops/sec ±0.43% (90 runs sampled)
assert.deepStrictEqual x 456 ops/sec ±0.71% (88 runs sampled)

The fastest is fast-deep-equal

To run benchmark (requires node.js 6+):

npm run benchmark

Please note: this benchmark runs against the available test cases. To choose the most performant library for your application, it is recommended to benchmark against your data and to NOT expect this benchmark to reflect the performance difference in your application.

Enterprise support

fast-deep-equal package is a part of Tidelift enterprise subscription - it provides a centralised commercial support to open-source software users, in addition to the support provided by software maintainers.

Security contact

To report a security vulnerability, please use the Tidelift security contact. Tidelift will coordinate the fix and disclosure. Please do NOT report security vulnerability via GitHub issues.