Run results for: Checking for presence of object key

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser: Chrome 132

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

! – last element

176.8M/s

typeof – first element

167.7M/s

in – last element

167.1M/s

! – first element

165.9M/s

in – first element

165.4M/s

typeof – last element

159.4M/s

View exact numbers

Script Preparation code:

var obj = {
   'first' : 1,
   'is' : 1,
   'some' : 1,
   'nice' : 1,
   'test' : 1,
   'last' : 1
}

Tests: