When your computer slows down, oftentimes its because there's a program that's taking up too much memory or CPU resources. Web browsers like Internet Explorer, Safari, Firefox and Chrome are to blame. You'll need to determine what resources your browser is using so you can eliminate the resource hogs and return your computer to the performance you had before.
Why Do Certain Browsers Run Slow?
Web browsers can display many pages in separate tabs. Web pages have increased in complexity and most browsers also support "extensions" or "plugins" that add features like password management, ad blocking, pop up blocker and more. With more load to it, each tab and every extension uses its own portion of computer memory.
This prevents malware on a web page from accessing other resources in your browser. And if one process crashes, it’s less likely to affect the others.
How to find the memory succubus?
Check if your web browser is using more memory or CPU than it should. You can see this in Windows by accessing Task Manager by holding down the CTRL and SHIFT keys, and then press the ESC key.
Click on Processes tab when the popup window appears.
On a Mac, open the applications folder and then Utilities folder and click on the Activity Monitor program.
Both Task Manager and Activity Monitor show running processes, called “Image Name” in Windows and “Process Name” on a Mac. Next to them is the percentage of the total CPU and memory resources its consuming. Click the header of a column, "Memory" to sort by that info and find the biggest memory uers.
For example, a single web page with video may use 20-30% of your CPU, and a few of those or any more will take up 50%. This will affect the performance of your computer. If the memory is used by all of your browser processes combined exceeds one-half of your computer's memory, your browser is likely the culprit.
On a Mac or PC, click the wrench icon in the upper right of your toolbar, select “Tools” and choose “Task Manager” to get a list of processes.
In Firefox on a Mac or PC, type “about:memory” in the address bar and press Enter. You’ll see the amount of memory processes are using, though not the CPU usage. You'll be able to see which tab you need to cut to track down the memory hogging extension or web page.
The easiest fix:
Closing your browser and reopening it is often the easiest fix.