This website will help you decide if another website is down or up (Online or Offline). You can chek every website without any limits. You can check websites from any country with any domain.
You can even check subdomains and free domain websites.
Also you can check another informations about searched website like Whois, Location, IP address... Sometimes you have problem with your DNS.
Please if stil have problem with checked website (Our website showing that checked website is UP but it is DOWN for you) you need to refresh your DNS or use OPEN DNS (22.214.171.124 and 126.96.36.199). You can use Google DNS too (188.8.131.52 and 184.108.40.206)
After changing your DNS ip addresses you need to do "Flush DNS". In your CMD type "ipconfig /flushdns". After this your website should work.