Round organiser? Order addresses by distance?

Anybody know of a program that can organise my addresses by distance so as to find the fastest route? As I've been building my round over the last year I've slowly added more and more customers to my spreadsheet and it's started to turn into something I dread looking at ?. At the moment I'm being very lazy and inefficient because I'm driving all around my town when I should be doing all the houses in 1 area then move onto the next, it's just common sense. 

Have you used any software or program online that would do this? I had a quick search around and then thought I'd ask on here before researching online a bit more.

Thanks, Jake

we use squeegee it does the job for us

Search for optimap, you can plot rounds and plan routes, it’s very useful.

Thanks guys. I like the optimap that looks like what I'm after, just gave it a quick try. I like that you don't need to download an app to test it out.