Do Chrome extensions slow down your computer?
Some Chrome extensions slow down your computer, but most do not in a way you would notice. The ones that do usually run heavy work on every page you open, or keep busy in the background when you are not using them. Chrome’s own Task Manager shows what each extension uses, so you can find the one that costs you and switch it off.
Where an extension does its work
An extension can have up to three parts, and each one uses your computer differently.
- The background part. Chrome wakes it when it has something to do, such as a timer going off or a button being pressed, and puts it back to sleep after a short while of nothing happening. Chrome has phased out the older kind of extension that could keep a background page running all day, so this part costs little.
- The part that runs inside pages. An extension that works on the sites you visit adds its own code to every page it is allowed on. This is where most slowdowns come from. An extension that scans every page for prices, checks every text box as you type, or filters every request a page makes is doing real work on every tab.
- The menu. The small window that opens from the toolbar runs only while it is open.
So the question to ask of any extension is: what does it do on every page, and how much of it?
Signs an extension is slowing you down
- Chrome feels slow while your other programs feel normal.
- Pages take longer to load, or typing lags in text boxes.
- Your fan spins up, or your battery runs down, with only a few tabs open.
- The problem goes away in an Incognito window. Extensions are off there unless you have allowed them, which makes it a quick test.
How to find the slow extension
Use Chrome’s Task Manager
Chrome has its own Task Manager, separate from your computer’s. Open the Chrome menu (the three dots at the top right), then More tools, then Task manager. On Windows and ChromeOS, Shift and Esc together opens it too.
It lists every tab and every extension, with how much memory, processor and network each one uses. Select a column heading to sort by it.
- An extension high on the CPU list while you are doing nothing is worth a closer look.
- Work an extension does inside a page is counted under that tab, not under the extension’s own name. If one tab is busy, hide or switch off the extension on that site and watch whether the tab’s number drops.
Switch them off one at a time
- Type chrome://extensions in the address bar.
- Turn every extension off with its switch.
- Use Chrome normally for a while. If it is quick again, an extension was the cause.
- Turn them back on one at a time, and note when the slowness returns.
Let Chrome save memory for you
Under Settings then Performance, Chrome has Memory Saver, which frees memory from tabs you have not looked at for a while, and Energy Saver, which cuts background work when your battery is low. Both help whether or not an extension is the cause.
How many extensions is too many?
There is no fixed number. Ten light extensions can cost less than one heavy one, so the count matters less than what each one does.
A better rule: if you have not used an extension in a month, remove it. Fewer extensions also means fewer that can see your pages. Our article on what “Read and change all your data on all websites” means explains what that permission allows and how to check an extension before you add it.
Limit where an extension runs
You do not have to choose between keeping an extension everywhere or removing it. Right-click its icon in the toolbar and open This can read and change site data. You can choose:
- When you click the extension, so it runs only when you ask
- On the site you are on, so it runs on that site only
- On all sites, the default for most
An extension you need on two or three sites does not need to run on all the others.
What about an animated pet in every tab?
We make one, Pawsome Family, and it runs on every page, so it is a fair question to ask of us. Here is what it does:
- It waits for the page. The pet starts after the page has finished loading, not while it loads.
- Nothing is downloaded page by page. Your pet’s drawing is saved on your computer once. The extension checks for changes to your pet every few hours in the background, not each time you open a page.
- It draws on the main page only, not inside the ads, videos and other frames a page contains.
- Background tabs rest. In a tab you are not looking at, the pet stops and waits.
- You can turn it down. The toolbar menu has Hide on this site, Pause for an hour, Hide in full screen, and a size setting.
The best way to judge any extension, ours included, is the Task Manager test above: open a busy page, note the tab’s numbers, then hide the pet and look again. Our help page on why your pet isn’t showing in your tabs shows where each setting is.
A pet that stays light
Pawsome Family turns 1 to 5 photos of your dog or cat into a small animated pet that walks, sits and naps along the bottom of your Chrome tabs. See the example husky.
One pet is free for 30 days, with no card needed.