A lot of people use the default DNS settings which they got from their ISP’s which are in most cases sufficient for most purposes but there are plenty of free options out there that you can use, e.g. Google DNS. Using a free tool called Namebench you can check and see whether your current DNS settings are optimized, and if they are not, you can choose the best free options offered by Namebench. Read this tutorial to find out which options you need to adjust and how to start this free tool.
To get started follow steps below
Step 1: We will need to download and install Namebench application from this link
Step 2: Once installation is finished start the app and choose your settings. Make sure that two top boxes are checked
Step 3: If you are concerned about network censorship, make sure that third box is also checked. Also if you want to help developers check the last box
Step 4: Once you are done click Start Benchmark button and wait until Namebench finish its testing’s. Depending of your system configurations it may take several minutes to finish.
Step 5: When Namebench testing’s are finished a browser tab will open offering you a list of DNS servers, and how much faster they are then the one you are currently using. Choose the one you prefer most.
With Namebench you can dramatically increase your web browsing speed and its quite easy to use it.