ToolsIs this website up?
Is this website up?: wikipedia.org
One measurement from our server in Vietnam: does the site load, its status code and response times.
Check whether a website is up
This tool loads the page once from our server in Vietnam and tells you whether it is up, slow or down, with the status code and the time of each step. Use it when someone says the site won’t open or feels slow.
The tool says it is up, but I still can’t open it?
The check runs from our server in Vietnam. If we can reach it and you can’t, the problem is usually your network, DNS or firewall: try another network (mobile data) or flush your DNS cache.
What is TTFB and how slow is too slow?
TTFB is the time from the start until the server sends the first byte of the page. We call a site slow when TTFB is over 1.5 seconds or the page takes over 4 seconds to load. High TTFB usually means an overloaded server, no caching, or a server far from its visitors.
The page returns 403 but the tool says it is up?
A 403 means the server answered but refused to show the page, usually because a firewall or bot protection blocks automated checks. Visitors using a browser may still get in normally.