Connection troubleshooting
Roughly half of all "the site is down" reports are something on the visitor's side. Here is how to find out which half you are in.
A browser gives you almost no information about where a request failed. The connection could have broken at your router, at your ISP, at a DNS resolver, at a CDN edge, or at the origin server - And the page looks identical in every case.
These guides take each layer in turn, with the tests that distinguish them. They are written for people who do not run networks for a living.
If you are not sure where to start, is it my internet, or the website? is the one most people need first, and when dns stops working follows on from it directly. If you would rather just find out whether a particular site is working, check it from our servers or look at what is failing right now.
All 9 guides in connection troubleshooting
Is it my internet, or the website?
A layered diagnostic for working out whether the fault is your device, your network, your ISP, DNS, or the website itself.
When DNS stops working
How DNS resolution fails, how to confirm it is the cause, and how to fix it - Including which resolver to switch to and why.
Clearing the DNS cache
Exact commands for flushing the DNS cache on every major platform, plus the browser and router caches people forget about.
Router and Wi-Fi problems
How to diagnose a router or Wi-Fi problem from the status lights, and the difference between a line fault, a Wi-Fi fault and congestion.
VPN and proxy problems
Why VPNs cause 403 errors, captcha loops, slow connections and half-loading pages - And how to identify which of those you have.
Browser-side causes
How browser caches, service workers, extensions and stale cookies break working websites, and the one test that rules out all four at once.
When your ISP is down
How to confirm an ISP outage, why cable outages affect one street and not the next, and what to do while you wait.
How to change your DNS settings
Step-by-step instructions for switching to 1.1.1.1, 8.8.8.8 or 9.9.9.9 on every major platform, and how to verify the change worked.
Choosing a DNS resolver
An honest comparison of Cloudflare 1.1.1.1, Google 8.8.8.8, Quad9 and the alternatives - Speed, privacy, filtering and reliability.