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

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser: Chrome 130

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
for-in	129.7 Ops/sec
Object.keys	108.2 Ops/sec

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) { const b = obj[key] } }
Object.keys
for (var i=10000; i > 0; i--) { const keys = Object.keys(obj) for (let i = 0; i < keys.length; i++) { const b = obj[keys[i]] } }