How to judge a Chrome extension before you install it
The Chrome Web Store reviews what it lists, and things still get through. It is also not designed to tell you whether an extension has been abandoned, sold, or built on a platform Chrome no longer runs. These are the checks that are worth your time, roughly in order of how much they tell you.
Does what it asks for match what it does
This is the one check that matters most, and the only one that is hard to fake. An extension that changes your new tab background does not need to read every page you open. One that blocks ads does. The question is never "is this permission dangerous" but "does this extension need it".
30% of the 49,702 extensions we have examined can read and change data on every site. That is too many for the request itself to be a red flag — but it makes the mismatch between job and access the thing to look at. How to read the permission list.
When was it last updated
An extension that has not shipped a release in three years is not being watched. It receives no security fixes, and it will not be adapted when Chrome changes underneath it. The store shows the date but does not draw attention to it. We keep a list of the extensions we track that nobody has touched in over two years.
Is it on a platform Chrome still runs
Extensions built on Manifest V2 stopped working in Chrome 138, released in July 2025. Some are still listed in the store, so it is entirely possible to install one today and get nothing. Our list of the ones still listed covers what we have found so far.
Has the publisher changed
Established extensions with large user bases are bought and sold, and the new owner inherits every permission the old one was granted, silently. The store does not show this. It is one of the things we watch for and record on an extension's page when we see it happen.
The signals that tell you less than you would think
- Star rating. It measures whether people liked it, which is not the same question, and it is trivially inflated.
- User count. Popular extensions have been compromised before, and a small install base is often just a small useful tool.
- Being in the store. Necessary, nowhere near sufficient.
After you install
Narrow the site access if you can, and look again in six months. Extensions change hands, gain permissions in updates, and get abandoned, and none of that announces itself. You can look up any extension you already have on our check page.