Run results for: for-in vs object.keys vs for..of object.keys

Run details:

User agent: Mozilla/5.0 (Android 11; Mobile; rv:91.0) Gecko/91.0 Firefox/91.0

Browser: Firefox Mobile 91

Operating system: Android

Device Platform: Mobile

Date tested: 3 years ago

Script Preparation code:

var obj = {
  'a': 1,
  'b': 1,
  'c': 1,
  'd': 1,
  'e': 1,
  'f': 1,
  'g': 1
};

Tests:

for-in
for (var i=10000; i > 0; i--) { for (var key in obj) { console.log(key); } }
Object.keys
for (var i=10000; i > 0; i--) { Object.keys(obj).forEach(key => console.log(key)); }
for-of object.keys
for (var i=10000; i > 0; i--) { for (const key of Object.keys(obj)) { console.log(key) } }