ERR_BLOCKED_BY_CLIENT
The request never left your browser: an extension, most often an ad blocker, stopped it because the address matched one of its rules.
Quick checks
- Open the page in a private window with extensions disabled.
- Pause your ad blocker for this site.
Fixes on Mac
Find the extension
- Go to
chrome://extensionsand turn extensions off one at a time, reloading after each. - Ad blockers, privacy extensions and antivirus extensions are the usual suspects.
- Go to
Allow the site
- Open the blocker's menu on the page and choose to allow or pause it for this site.
Fixes on Windows
Same steps
- Disable extensions at
chrome://extensionsone by one, or allow-list the site.
- Disable extensions at
Other devices
Managed devices
- On a work or school device, an administrator policy may block the request; ask IT.
Still not working?
Developers: if your own requests are blocked, the URL or file name probably matches a filter list (paths like /ads/, /banner, analytics.js). Rename the path, or serve the script from your own domain if it isn't actually tracking.
See what’s happening
DNS-level blockers work differently from extensions: a blocked name never gets a connection in LightAtom's connections view.
Frequently asked questions
What does ERR_BLOCKED_BY_CLIENT mean?
Something inside the browser, nearly always an extension like an ad blocker, blocked the request before it was sent.
Is ERR_BLOCKED_BY_CLIENT a problem?
Usually not: it's your blocker doing its job. Allow the site only if something you need, like a video or checkout, doesn't work.
Why does it appear in DevTools on my site?
Your page requested a URL that matches a blocker's filter list. Visitors with blockers won't load it either; rename it or remove it if it's not needed.