Benchmark: String Concatenation

Script Preparation code:

var str1 = "", 
    str2 = "", 
    str3 = "", 
    sArr1 = [],
sArr2 = new Array(30000);

Tests:

standard string append
// standard string append for (var i = 30000; i > 0; i--) { str1 += "String concatenation. "; }
array join
for (var i = 30000; i > 0; i--) { sArr1[i] = "String concatenation. "; } str2 = sArr1.join("");
array join 2
for (var i = 30000; i > 0; i--) { sArr2[i] = "String concatenation. "; } str3 = sArr2.join("");

Rendered benchmark preparation results:

Previous results

ⓘ Get performance results from real users on your website with Request Metrics.

Latest run results:

Run details: (Test run date: 4 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/115.0.0.0 Safari/537.36

Browser/OS: Chrome 115 on Windows

String Concatenation (version: 5)