Run results for: parseInt vs toString vs string literal vs + empty string

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 11.2; rv:86.0) Gecko/20100101 Firefox/86.0

Browser: Firefox 86

Operating system: Mac OS X 11.2

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
parseInt a number	12840250.0 Ops/sec
parseInt a string	2307147.2 Ops/sec
toString a number	4489478.0 Ops/sec
toString a string	22242738.0 Ops/sec
string literal a number	4594748.5 Ops/sec
string literal a string	24887598.0 Ops/sec
add empty string to number	4463590.5 Ops/sec
add empty string to string	18094142.0 Ops/sec

Script Preparation code:

var numbers = [1, 12, 123, 1234, 12345, 123456, 1234567, 12345678, 123456789];
var strNumbers = ["1", "12", "123", "1234", "12345", "123456", "1234567", "12345678", "123456789"];

Tests:

parseInt a number
numbers.forEach(n => parseInt(n, 10));
parseInt a string
strNumbers.forEach(n => parseInt(n, 10));
toString a number
numbers.forEach(n => n.toString());
toString a string
strNumbers.forEach(n => n.toString());
string literal a number
numbers.forEach(n => `${n}`);
string literal a string
strNumbers.forEach(n => `${n}`);
add empty string to number
numbers.forEach(n => n + "");
add empty string to string
strNumbers.forEach(n => n + "");

Run results for: parseInt vs toString vs string literal vs + empty string

parseInt a number

parseInt a string

toString a number

toString a string

string literal a number

string literal a string

add empty string to number

add empty string to string