What's the difference between .substr(0,1) or .charAt(0)?

Question

We were wondering in this thread if there was a real difference between the use of .substr(0,1) and the use of .charAt(0) when you want to get the

Answer 1

Measuring it is the key!

Go to http://jsperf.com/substr-or-charat to benchmark it yourself.

substr(0,1) runs at 21,100,301 operations per second on my machine, charAt(0) runs 550,852,974 times per second.

I suspect that charAt accesses the string as an array internally, rather than splitting the string.

As found in the comments, accessing the char directly using string[0] is slightly faster than using charAt(0).