Benchmark: simple deep copy comparison

Script Preparation code:

var x = [
  {
    "_id": "63b2e52d50eca4c87ff36b49",
    "index": 0,
    "guid": "fcd1d24d-adda-4685-b408-5925d9f142ef",
    "isActive": true,
    "balance": "$3,153.72",
    "picture": "http://placehold.it/32x32",
    "age": 23,
    "eyeColor": "brown",
    "name": "Lindsey Reed",
    "gender": "female",
    "company": "SILODYNE",
    "email": "lindseyreed@silodyne.com",
    "phone": "+1 (914) 459-2759",
    "address": "384 McDonald Avenue, Kimmell, Nebraska, 2194",
    "about": "Deserunt adipisicing labore esse culpa adipisicing consequat dolor voluptate ad adipisicing magna. Sint nostrud Lorem minim minim adipisicing commodo adipisicing reprehenderit id sint sint. Labore do occaecat veniam aute enim voluptate adipisicing sit dolor minim. Laborum ut laboris pariatur dolore culpa consectetur aute reprehenderit ea irure qui occaecat excepteur. Nulla in duis anim labore elit consectetur aliquip nisi eu Lorem reprehenderit commodo.\r\n",
    "registered": "2018-03-02T05:03:34 -01:00",
    "latitude": 84.860559,
    "longitude": 91.806106,
    "tags": [
      "reprehenderit",
      "eiusmod",
      "tempor",
      "laborum",
      "eu",
      "anim",
      "ea"
    ],
    "friends": [
      {
        "id": 0,
        "name": "Odessa Talley"
      },
      {
        "id": 1,
        "name": "Miranda Winters"
      },
      {
        "id": 2,
        "name": "Wendy Stout"
      }
    ],
    "greeting": "Hello, Lindsey Reed! You have 9 unread messages.",
    "favoriteFruit": "strawberry"
  },
  {
    "_id": "63b2e52d9c663a1ac78c8786",
    "index": 1,
    "guid": "8cf2ebad-34c3-40d1-b8bb-d89e16e77d36",
    "isActive": false,
    "balance": "$2,902.82",
    "picture": "http://placehold.it/32x32",
    "age": 23,
    "eyeColor": "brown",
    "name": "Violet Cameron",
    "gender": "female",
    "company": "PROXSOFT",
    "email": "violetcameron@proxsoft.com",
    "phone": "+1 (861) 439-2178",
    "address": "720 Cambridge Place, Charco, Colorado, 7619",
    "about": "Qui aliqua velit qui in nostrud duis quis nostrud tempor excepteur nulla quis pariatur tempor. Aliqua dolore aute magna aliquip mollit aliquip tempor laborum proident non deserunt ad adipisicing tempor. Nisi esse adipisicing non commodo do in ad nulla fugiat aute. Cillum pariatur mollit non commodo culpa duis proident ad dolore occaecat cupidatat.\r\n",
    "registered": "2017-12-24T10:30:37 -01:00",
    "latitude": 6.186006,
    "longitude": 38.698713,
    "tags": [
      "anim",
      "non",
      "cillum",
      "laborum",
      "labore",
      "nostrud",
      "quis"
    ],
    "friends": [
      {
        "id": 0,
        "name": "Dejesus Fuentes"
      },
      {
        "id": 1,
        "name": "Hillary Jacobs"
      },
      {
        "id": 2,
        "name": "Darlene Todd"
      }
    ],
    "greeting": "Hello, Violet Cameron! You have 3 unread messages.",
    "favoriteFruit": "strawberry"
  },
  {
    "_id": "63b2e52d0b0a79327838b0da",
    "index": 2,
    "guid": "6ee3eb6b-e17e-4072-938d-9d30b39d4839",
    "isActive": false,
    "balance": "$2,310.48",
    "picture": "http://placehold.it/32x32",
    "age": 21,
    "eyeColor": "brown",
    "name": "Todd Serrano",
    "gender": "male",
    "company": "NAMEBOX",
    "email": "toddserrano@namebox.com",
    "phone": "+1 (987) 585-2991",
    "address": "763 Barwell Terrace, Dodge, New Jersey, 4706",
    "about": "Dolor quis minim occaecat ullamco id est consectetur ad aliqua duis pariatur deserunt. Laboris nisi qui nostrud minim elit magna eu id sint non sint ex ullamco. Incididunt nisi labore aliquip magna aute proident reprehenderit fugiat commodo ullamco. Est proident laborum incididunt nulla tempor consectetur irure cupidatat. Et dolore laborum aliqua minim non eiusmod commodo aliqua nisi cupidatat voluptate ut deserunt mollit. Nisi ad ipsum consequat ut sit qui ut reprehenderit dolore nostrud.\r\n",
    "registered": "2015-08-18T10:48:52 -02:00",
    "latitude": -56.539321,
    "longitude": -0.832709,
    "tags": [
      "eiusmod",
      "proident",
      "fugiat",
      "id",
      "nisi",
      "ipsum",
      "tempor"
    ],
    "friends": [
      {
        "id": 0,
        "name": "Amie Mcclure"
      },
      {
        "id": 1,
        "name": "Decker Williamson"
      },
      {
        "id": 2,
        "name": "Gutierrez Klein"
      }
    ],
    "greeting": "Hello, Todd Serrano! You have 4 unread messages.",
    "favoriteFruit": "strawberry"
  },
  {
    "_id": "63b2e52d222b5d212ac163c7",
    "index": 3,
    "guid": "c4c2288b-d718-42ae-88c9-cfc85b069578",
    "isActive": true,
    "balance": "$3,713.06",
    "picture": "http://placehold.it/32x32",
    "age": 39,
    "eyeColor": "green",
    "name": "Jimmie Spears",
    "gender": "female",
    "company": "VITRICOMP",
    "email": "jimmiespears@vitricomp.com",
    "phone": "+1 (891) 543-3465",
    "address": "168 Senator Street, Eastmont, Maine, 4088",
    "about": "Id elit commodo quis labore ipsum voluptate nostrud minim dolor et. Magna consectetur minim est labore nostrud voluptate laborum deserunt non ipsum ea occaecat est nulla. Consectetur aliquip adipisicing veniam ut ea enim nisi adipisicing do proident. Esse do nisi anim ipsum reprehenderit cillum sint. Ad qui adipisicing consequat duis excepteur veniam est Lorem sunt sunt.\r\n",
    "registered": "2020-07-31T11:02:23 -02:00",
    "latitude": 83.343716,
    "longitude": -131.584608,
    "tags": [
      "consectetur",
      "ipsum",
      "minim",
      "quis",
      "quis",
      "nulla",
      "cillum"
    ],
    "friends": [
      {
        "id": 0,
        "name": "Mia Park"
      },
      {
        "id": 1,
        "name": "Muriel Adkins"
      },
      {
        "id": 2,
        "name": "Amber Reyes"
      }
    ],
    "greeting": "Hello, Jimmie Spears! You have 9 unread messages.",
    "favoriteFruit": "banana"
  },
  {
    "_id": "63b2e52d739458e938352ca7",
    "index": 4,
    "guid": "b3a0b156-ce38-4549-b5a2-1fa5fb6715ff",
    "isActive": true,
    "balance": "$2,327.00",
    "picture": "http://placehold.it/32x32",
    "age": 25,
    "eyeColor": "blue",
    "name": "Pennington Mendez",
    "gender": "male",
    "company": "QUIZMO",
    "email": "penningtonmendez@quizmo.com",
    "phone": "+1 (832) 438-2788",
    "address": "886 Drew Street, Groton, Ohio, 9666",
    "about": "Ad fugiat est officia Lorem adipisicing mollit ex nisi ipsum. Irure aliqua in amet reprehenderit. Culpa Lorem ipsum aute eiusmod velit elit.\r\n",
    "registered": "2018-07-13T04:33:49 -02:00",
    "latitude": -44.124601,
    "longitude": 141.036093,
    "tags": [
      "officia",
      "nostrud",
      "velit",
      "ut",
      "et",
      "reprehenderit",
      "do"
    ],
    "friends": [
      {
        "id": 0,
        "name": "Kelly Padilla"
      },
      {
        "id": 1,
        "name": "Chase Ellis"
      },
      {
        "id": 2,
        "name": "Angie Savage"
      }
    ],
    "greeting": "Hello, Pennington Mendez! You have 4 unread messages.",
    "favoriteFruit": "strawberry"
  },
  {
    "_id": "63b2e52dc02a8273d96417eb",
    "index": 5,
    "guid": "b20e2cf2-9867-4788-bf5b-77e517ba696f",
    "isActive": true,
    "balance": "$1,796.46",
    "picture": "http://placehold.it/32x32",
    "age": 24,
    "eyeColor": "green",
    "name": "Virginia Harrell",
    "gender": "female",
    "company": "HALAP",
    "email": "virginiaharrell@halap.com",
    "phone": "+1 (904) 597-3148",
    "address": "212 Classon Avenue, Forbestown, Tennessee, 5406",
    "about": "Cillum velit nisi dolor eu incididunt consectetur in officia et laboris incididunt qui. Officia dolor in amet consectetur eu esse minim dolore eu ex ipsum aliqua esse. Proident nisi sit sint exercitation deserunt ex voluptate mollit occaecat. Quis mollit reprehenderit quis nulla irure aliquip in. Voluptate fugiat do fugiat sint veniam. Enim aute ex proident sit magna voluptate occaecat officia velit in aute excepteur eiusmod.\r\n",
    "registered": "2016-05-19T05:54:00 -02:00",
    "latitude": 58.623149,
    "longitude": -100.201165,
    "tags": [
      "sint",
      "do",
      "voluptate",
      "cupidatat",
      "Lorem",
      "magna",
      "cupidatat"
    ],
    "friends": [
      {
        "id": 0,
        "name": "Burns Jenkins"
      },
      {
        "id": 1,
        "name": "Lamb Dickson"
      },
      {
        "id": 2,
        "name": "Beverley Andrews"
      }
    ],
    "greeting": "Hello, Virginia Harrell! You have 7 unread messages.",
    "favoriteFruit": "banana"
  },
  {
    "_id": "63b2e52dd6dc4c8ddaa6cf64",
    "index": 6,
    "guid": "054a97bf-2be2-4707-b6d5-1863617dac1b",
    "isActive": false,
    "balance": "$3,374.66",
    "picture": "http://placehold.it/32x32",
    "age": 20,
    "eyeColor": "green",
    "name": "Lizzie Lambert",
    "gender": "female",
    "company": "MINGA",
    "email": "lizzielambert@minga.com",
    "phone": "+1 (977) 429-2396",
    "address": "565 Linwood Street, Jackpot, Oklahoma, 4779",
    "about": "Duis aliquip et culpa non aute non officia. Esse eu dolore anim aliquip occaecat. Occaecat dolor ad enim ullamco laborum duis aliquip dolore adipisicing occaecat est non quis sint.\r\n",
    "registered": "2016-05-18T08:22:31 -02:00",
    "latitude": -64.51267,
    "longitude": 148.522349,
    "tags": [
      "ad",
      "magna",
      "incididunt",
      "do",
      "do",
      "minim",
      "irure"
    ],
    "friends": [
      {
        "id": 0,
        "name": "Wynn Travis"
      },
      {
        "id": 1,
        "name": "Carey Ross"
      },
      {
        "id": 2,
        "name": "Christian Nelson"
      }
    ],
    "greeting": "Hello, Lizzie Lambert! You have 7 unread messages.",
    "favoriteFruit": "apple"
  }
];

Tests:

JSON.parse(JSON.stringify())
var result = JSON.parse(JSON.stringify(x));
structuredClone
var result = structuredClone(x);
Spread op
var result = {...x};
Object.assign()
var result = Object.assign(x);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
JSON.parse(JSON.stringify())
structuredClone
Spread op
Object.assign()

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36

Browser/OS: Chrome 107 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
JSON.parse(JSON.stringify())	37131.1 Ops/sec
structuredClone	39087.3 Ops/sec
Spread op	1531912.0 Ops/sec
Object.assign()	9500514.0 Ops/sec

simple deep copy comparison (version: 0)

compares benchmarks of a few (deep) copy methods

Comparing performance of: JSON.parse(JSON.stringify()) vs structuredClone vs Spread op vs Object.assign()

Created: one year ago by: Guest

Jump to the latest result

JSON.parse(JSON.stringify())

structuredClone

Spread op

Object.assign()

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A