Run results for: Delete vs set undefined

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:137.0) Gecko/20100101 Firefox/137.0

Browser: Firefox 137

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Set undefined

213.3M/s

Delete

14.0M/s

View exact numbers

Test name	Executions per second
✓ Set undefined	213,320,320 Ops/sec
Delete	14,023,914 Ops/sec

Script Preparation code:

var obj = {a:1, b:2, c:3, d:4};

Tests:

Delete
delete obj.a; delete obj.b; delete obj.c; delete obj.d;
Set undefined
obj.a = undefined; obj.b = undefined; obj.c = undefined; obj.d = undefined;